logic and critical thinking freshman course chapter one

Introduction to Logic and Critical Thinking

(10 reviews)

Matthew Van Cleave, Lansing Community College

Copyright Year: 2016

Publisher: Matthew J. Van Cleave

Language: English

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Reviewed by "yusef" Alexander Hayes, Professor, North Shore Community College on 6/9/21

Formal and informal reasoning, argument structure, and fallacies are covered comprehensively, meeting the author's goal of both depth and succinctness. read more

Comprehensiveness rating: 5 see less

Formal and informal reasoning, argument structure, and fallacies are covered comprehensively, meeting the author's goal of both depth and succinctness.

Content Accuracy rating: 5

The book is accurate.

Relevance/Longevity rating: 5

While many modern examples are used, and they are helpful, they are not necessarily needed. The usefulness of logical principles and skills have proved themselves, and this text presents them clearly with many examples.

Clarity rating: 5

It is obvious that the author cares about their subject, audience, and students. The text is comprehensible and interesting.

Consistency rating: 5

The format is easy to understand and is consistent in framing.

Modularity rating: 5

This text would be easy to adapt.

Organization/Structure/Flow rating: 5

The organization is excellent, my one suggestion would be a concluding chapter.

Interface rating: 5

I accessed the PDF version and it would be easy to work with.

Grammatical Errors rating: 5

The writing is excellent.

Cultural Relevance rating: 5

This is not an offensive text.

Reviewed by Susan Rottmann, Part-time Lecturer, University of Southern Maine on 3/2/21

I reviewed this book for a course titled "Creative and Critical Inquiry into Modern Life." It won't meet all my needs for that course, but I haven't yet found a book that would. I wanted to review this one because it states in the preface that it... read more

Comprehensiveness rating: 4 see less

I reviewed this book for a course titled "Creative and Critical Inquiry into Modern Life." It won't meet all my needs for that course, but I haven't yet found a book that would. I wanted to review this one because it states in the preface that it fits better for a general critical thinking course than for a true logic course. I'm not sure that I'd agree. I have been using Browne and Keeley's "Asking the Right Questions: A Guide to Critical Thinking," and I think that book is a better introduction to critical thinking for non-philosophy majors. However, the latter is not open source so I will figure out how to get by without it in the future. Overall, the book seems comprehensive if the subject is logic. The index is on the short-side, but fine. However, one issue for me is that there are no page numbers on the table of contents, which is pretty annoying if you want to locate particular sections.

Content Accuracy rating: 4

I didn't find any errors. In general the book uses great examples. However, they are very much based in the American context, not for an international student audience. Some effort to broaden the chosen examples would make the book more widely applicable.

Relevance/Longevity rating: 4

I think the book will remain relevant because of the nature of the material that it addresses, however there will be a need to modify the examples in future editions and as the social and political context changes.

Clarity rating: 3

The text is lucid, but I think it would be difficult for introductory-level students who are not philosophy majors. For example, in Browne and Keeley's "Asking the Right Questions: A Guide to Critical Thinking," the sub-headings are very accessible, such as "Experts cannot rescue us, despite what they say" or "wishful thinking: perhaps the biggest single speed bump on the road to critical thinking." By contrast, Van Cleave's "Introduction to Logic and Critical Thinking" has more subheadings like this: "Using your own paraphrases of premises and conclusions to reconstruct arguments in standard form" or "Propositional logic and the four basic truth functional connectives." If students are prepared very well for the subject, it would work fine, but for students who are newly being introduced to critical thinking, it is rather technical.

It seems to be very consistent in terms of its terminology and framework.

Modularity rating: 4

The book is divided into 4 chapters, each having many sub-chapters. In that sense, it is readily divisible and modular. However, as noted above, there are no page numbers on the table of contents, which would make assigning certain parts rather frustrating. Also, I'm not sure why the book is only four chapter and has so many subheadings (for instance 17 in Chapter 2) and a length of 242 pages. Wouldn't it make more sense to break up the book into shorter chapters? I think this would make it easier to read and to assign in specific blocks to students.

Organization/Structure/Flow rating: 4

The organization of the book is fine overall, although I think adding page numbers to the table of contents and breaking it up into more separate chapters would help it to be more easily navigable.

Interface rating: 4

The book is very simply presented. In my opinion it is actually too simple. There are few boxes or diagrams that highlight and explain important points.

The text seems fine grammatically. I didn't notice any errors.

The book is written with an American audience in mind, but I did not notice culturally insensitive or offensive parts.

Overall, this book is not for my course, but I think it could work well in a philosophy course.

Reviewed by Daniel Lee, Assistant Professor of Economics and Leadership, Sweet Briar College on 11/11/19

This textbook is not particularly comprehensive (4 chapters long), but I view that as a benefit. In fact, I recommend it for use outside of traditional logic classes, but rather interdisciplinary classes that evaluate argument read more

Comprehensiveness rating: 3 see less

This textbook is not particularly comprehensive (4 chapters long), but I view that as a benefit. In fact, I recommend it for use outside of traditional logic classes, but rather interdisciplinary classes that evaluate argument

To the best of my ability, I regard this content as accurate, error-free, and unbiased

The book is broadly relevant and up-to-date, with a few stray temporal references (sydney olympics, particular presidencies). I don't view these time-dated examples as problematic as the logical underpinnings are still there and easily assessed

Clarity rating: 4

My only pushback on clarity is I didn't find the distinction between argument and explanation particularly helpful/useful/easy to follow. However, this experience may have been unique to my class.

To the best of my ability, I regard this content as internally consistent

I found this text quite modular, and was easily able to integrate other texts into my lessons and disregard certain chapters or sub-sections

The book had a logical and consistent structure, but to the extent that there are only 4 chapters, there isn't much scope for alternative approaches here

No problems with the book's interface

The text is grammatically sound

Cultural Relevance rating: 4

Perhaps the text could have been more universal in its approach. While I didn't find the book insensitive per-se, logic can be tricky here because the point is to evaluate meaningful (non-trivial) arguments, but any argument with that sense of gravity can also be traumatic to students (abortion, death penalty, etc)

No additional comments

Reviewed by Lisa N. Thomas-Smith, Graduate Part-time Instructor, CU Boulder on 7/1/19

The text covers all the relevant technical aspects of introductory logic and critical thinking, and covers them well. A separate glossary would be quite helpful to students. However, the terms are clearly and thoroughly explained within the text,... read more

The text covers all the relevant technical aspects of introductory logic and critical thinking, and covers them well. A separate glossary would be quite helpful to students. However, the terms are clearly and thoroughly explained within the text, and the index is very thorough.

The content is excellent. The text is thorough and accurate with no errors that I could discern. The terminology and exercises cover the material nicely and without bias.

The text should easily stand the test of time. The exercises are excellent and would be very helpful for students to internalize correct critical thinking practices. Because of the logical arrangement of the text and the many sub-sections, additional material should be very easy to add.

The text is extremely clearly and simply written. I anticipate that a diligent student could learn all of the material in the text with little additional instruction. The examples are relevant and easy to follow.

The text did not confuse terms or use inconsistent terminology, which is very important in a logic text. The discipline often uses multiple terms for the same concept, but this text avoids that trap nicely.

The text is fairly easily divisible. Since there are only four chapters, those chapters include large blocks of information. However, the chapters themselves are very well delineated and could be easily broken up so that parts could be left out or covered in a different order from the text.

The flow of the text is excellent. All of the information is handled solidly in an order that allows the student to build on the information previously covered.

The PDF Table of Contents does not include links or page numbers which would be very helpful for navigation. Other than that, the text was very easy to navigate. All the images, charts, and graphs were very clear

I found no grammatical errors in the text.

Cultural Relevance rating: 3

The text including examples and exercises did not seem to be offensive or insensitive in any specific way. However, the examples included references to black and white people, but few others. Also, the text is very American specific with many examples from and for an American audience. More diversity, especially in the examples, would be appropriate and appreciated.

Reviewed by Leslie Aarons, Associate Professor of Philosophy, CUNY LaGuardia Community College on 5/16/19

This is an excellent introductory (first-year) Logic and Critical Thinking textbook. The book covers the important elementary information, clearly discussing such things as the purpose and basic structure of an argument; the difference between an... read more

This is an excellent introductory (first-year) Logic and Critical Thinking textbook. The book covers the important elementary information, clearly discussing such things as the purpose and basic structure of an argument; the difference between an argument and an explanation; validity; soundness; and the distinctions between an inductive and a deductive argument in accessible terms in the first chapter. It also does a good job introducing and discussing informal fallacies (Chapter 4). The incorporation of opportunities to evaluate real-world arguments is also very effective. Chapter 2 also covers a number of formal methods of evaluating arguments, such as Venn Diagrams and Propositional logic and the four basic truth functional connectives, but to my mind, it is much more thorough in its treatment of Informal Logic and Critical Thinking skills, than it is of formal logic. I also appreciated that Van Cleave’s book includes exercises with answers and an index, but there is no glossary; which I personally do not find detracts from the book's comprehensiveness.

Overall, Van Cleave's book is error-free and unbiased. The language used is accessible and engaging. There were no glaring inaccuracies that I was able to detect.

Van Cleave's Textbook uses relevant, contemporary content that will stand the test of time, at least for the next few years. Although some examples use certain subjects like former President Obama, it does so in a useful manner that inspires the use of critical thinking skills. There are an abundance of examples that inspire students to look at issues from many different political viewpoints, challenging students to practice evaluating arguments, and identifying fallacies. Many of these exercises encourage students to critique issues, and recognize their own inherent reader-biases and challenge their own beliefs--hallmarks of critical thinking.

As mentioned previously, the author has an accessible style that makes the content relatively easy to read and engaging. He also does a suitable job explaining jargon/technical language that is introduced in the textbook.

Van Cleave uses terminology consistently and the chapters flow well. The textbook orients the reader by offering effective introductions to new material, step-by-step explanations of the material, as well as offering clear summaries of each lesson.

This textbook's modularity is really quite good. Its language and structure are not overly convoluted or too-lengthy, making it convenient for individual instructors to adapt the materials to suit their methodological preferences.

The topics in the textbook are presented in a logical and clear fashion. The structure of the chapters are such that it is not necessary to have to follow the chapters in their sequential order, and coverage of material can be adapted to individual instructor's preferences.

The textbook is free of any problematic interface issues. Topics, sections and specific content are accessible and easy to navigate. Overall it is user-friendly.

I did not find any significant grammatical issues with the textbook.

The textbook is not culturally insensitive, making use of a diversity of inclusive examples. Materials are especially effective for first-year critical thinking/logic students.

I intend to adopt Van Cleave's textbook for a Critical Thinking class I am teaching at the Community College level. I believe that it will help me facilitate student-learning, and will be a good resource to build additional classroom activities from the materials it provides.

Reviewed by Jennie Harrop, Chair, Department of Professional Studies, George Fox University on 3/27/18

While the book is admirably comprehensive, its extensive details within a few short chapters may feel overwhelming to students. The author tackles an impressive breadth of concepts in Chapter 1, 2, 3, and 4, which leads to 50-plus-page chapters... read more

While the book is admirably comprehensive, its extensive details within a few short chapters may feel overwhelming to students. The author tackles an impressive breadth of concepts in Chapter 1, 2, 3, and 4, which leads to 50-plus-page chapters that are dense with statistical analyses and critical vocabulary. These topics are likely better broached in manageable snippets rather than hefty single chapters.

The ideas addressed in Introduction to Logic and Critical Thinking are accurate but at times notably political. While politics are effectively used to exemplify key concepts, some students may be distracted by distinct political leanings.

The terms and definitions included are relevant, but the examples are specific to the current political, cultural, and social climates, which could make the materials seem dated in a few years without intentional and consistent updates.

While the reasoning is accurate, the author tends to complicate rather than simplify -- perhaps in an effort to cover a spectrum of related concepts. Beginning readers are likely to be overwhelmed and under-encouraged by his approach.

Consistency rating: 3

The four chapters are somewhat consistent in their play of definition, explanation, and example, but the structure of each chapter varies according to the concepts covered. In the third chapter, for example, key ideas are divided into sub-topics numbering from 3.1 to 3.10. In the fourth chapter, the sub-divisions are further divided into sub-sections numbered 4.1.1-4.1.5, 4.2.1-4.2.2, and 4.3.1 to 4.3.6. Readers who are working quickly to master new concepts may find themselves mired in similarly numbered subheadings, longing for a grounded concepts on which to hinge other key principles.

Modularity rating: 3

The book's four chapters make it mostly self-referential. The author would do well to beak this text down into additional subsections, easing readers' accessibility.

The content of the book flows logically and well, but the information needs to be better sub-divided within each larger chapter, easing the student experience.

The book's interface is effective, allowing readers to move from one section to the next with a single click. Additional sub-sections would ease this interplay even further.

Grammatical Errors rating: 4

Some minor errors throughout.

For the most part, the book is culturally neutral, avoiding direct cultural references in an effort to remain relevant.

Reviewed by Yoichi Ishida, Assistant Professor of Philosophy, Ohio University on 2/1/18

This textbook covers enough topics for a first-year course on logic and critical thinking. Chapter 1 covers the basics as in any standard textbook in this area. Chapter 2 covers propositional logic and categorical logic. In propositional logic,... read more

This textbook covers enough topics for a first-year course on logic and critical thinking. Chapter 1 covers the basics as in any standard textbook in this area. Chapter 2 covers propositional logic and categorical logic. In propositional logic, this textbook does not cover suppositional arguments, such as conditional proof and reductio ad absurdum. But other standard argument forms are covered. Chapter 3 covers inductive logic, and here this textbook introduces probability and its relationship with cognitive biases, which are rarely discussed in other textbooks. Chapter 4 introduces common informal fallacies. The answers to all the exercises are given at the end. However, the last set of exercises is in Chapter 3, Section 5. There are no exercises in the rest of the chapter. Chapter 4 has no exercises either. There is index, but no glossary.

The textbook is accurate.

The content of this textbook will not become obsolete soon.

The textbook is written clearly.

The textbook is internally consistent.

The textbook is fairly modular. For example, Chapter 3, together with a few sections from Chapter 1, can be used as a short introduction to inductive logic.

The textbook is well-organized.

There are no interface issues.

I did not find any grammatical errors.

This textbook is relevant to a first semester logic or critical thinking course.

Reviewed by Payal Doctor, Associate Professro, LaGuardia Community College on 2/1/18

This text is a beginner textbook for arguments and propositional logic. It covers the basics of identifying arguments, building arguments, and using basic logic to construct propositions and arguments. It is quite comprehensive for a beginner... read more

This text is a beginner textbook for arguments and propositional logic. It covers the basics of identifying arguments, building arguments, and using basic logic to construct propositions and arguments. It is quite comprehensive for a beginner book, but seems to be a good text for a course that needs a foundation for arguments. There are exercises on creating truth tables and proofs, so it could work as a logic primer in short sessions or with the addition of other course content.

The books is accurate in the information it presents. It does not contain errors and is unbiased. It covers the essential vocabulary clearly and givens ample examples and exercises to ensure the student understands the concepts

The content of the book is up to date and can be easily updated. Some examples are very current for analyzing the argument structure in a speech, but for this sort of text understandable examples are important and the author uses good examples.

The book is clear and easy to read. In particular, this is a good text for community college students who often have difficulty with reading comprehension. The language is straightforward and concepts are well explained.

The book is consistent in terminology, formatting, and examples. It flows well from one topic to the next, but it is also possible to jump around the text without loosing the voice of the text.

The books is broken down into sub units that make it easy to assign short blocks of content at a time. Later in the text, it does refer to a few concepts that appear early in that text, but these are all basic concepts that must be used to create a clear and understandable text. No sections are too long and each section stays on topic and relates the topic to those that have come before when necessary.

The flow of the text is logical and clear. It begins with the basic building blocks of arguments, and practice identifying more and more complex arguments is offered. Each chapter builds up from the previous chapter in introducing propositional logic, truth tables, and logical arguments. A select number of fallacies are presented at the end of the text, but these are related to topics that were presented before, so it makes sense to have these last.

The text is free if interface issues. I used the PDF and it worked fine on various devices without loosing formatting.

1. The book contains no grammatical errors.

The text is culturally sensitive, but examples used are a bit odd and may be objectionable to some students. For instance, President Obama's speech on Syria is used to evaluate an extended argument. This is an excellent example and it is explained well, but some who disagree with Obama's policies may have trouble moving beyond their own politics. However, other examples look at issues from all political viewpoints and ask students to evaluate the argument, fallacy, etc. and work towards looking past their own beliefs. Overall this book does use a variety of examples that most students can understand and evaluate.

My favorite part of this book is that it seems to be written for community college students. My students have trouble understanding readings in the New York Times, so it is nice to see a logic and critical thinking text use real language that students can understand and follow without the constant need of a dictionary.

Reviewed by Rebecca Owen, Adjunct Professor, Writing, Chemeketa Community College on 6/20/17

This textbook is quite thorough--there are conversational explanations of argument structure and logic. I think students will be happy with the conversational style this author employs. Also, there are many examples and exercises using current... read more

This textbook is quite thorough--there are conversational explanations of argument structure and logic. I think students will be happy with the conversational style this author employs. Also, there are many examples and exercises using current events, funny scenarios, or other interesting ways to evaluate argument structure and validity. The third section, which deals with logical fallacies, is very clear and comprehensive. My only critique of the material included in the book is that the middle section may be a bit dense and math-oriented for learners who appreciate the more informal, informative style of the first and third section. Also, the book ends rather abruptly--it moves from a description of a logical fallacy to the answers for the exercises earlier in the text.

The content is very reader-friendly, and the author writes with authority and clarity throughout the text. There are a few surface-level typos (Starbuck's instead of Starbucks, etc.). None of these small errors detract from the quality of the content, though.

One thing I really liked about this text was the author's wide variety of examples. To demonstrate different facets of logic, he used examples from current media, movies, literature, and many other concepts that students would recognize from their daily lives. The exercises in this text also included these types of pop-culture references, and I think students will enjoy the familiarity--as well as being able to see the logical structures behind these types of references. I don't think the text will need to be updated to reflect new instances and occurrences; the author did a fine job at picking examples that are relatively timeless. As far as the subject matter itself, I don't think it will become obsolete any time soon.

The author writes in a very conversational, easy-to-read manner. The examples used are quite helpful. The third section on logical fallacies is quite easy to read, follow, and understand. A student in an argument writing class could benefit from this section of the book. The middle section is less clear, though. A student learning about the basics of logic might have a hard time digesting all of the information contained in chapter two. This material might be better in two separate chapters. I think the author loses the balance of a conversational, helpful tone and focuses too heavily on equations.

Consistency rating: 4

Terminology in this book is quite consistent--the key words are highlighted in bold. Chapters 1 and 3 follow a similar organizational pattern, but chapter 2 is where the material becomes more dense and equation-heavy. I also would have liked a closing passage--something to indicate to the reader that we've reached the end of the chapter as well as the book.

I liked the overall structure of this book. If I'm teaching an argumentative writing class, I could easily point the students to the chapters where they can identify and practice identifying fallacies, for instance. The opening chapter is clear in defining the necessary terms, and it gives the students an understanding of the toolbox available to them in assessing and evaluating arguments. Even though I found the middle section to be dense, smaller portions could be assigned.

The author does a fine job connecting each defined term to the next. He provides examples of how each defined term works in a sentence or in an argument, and then he provides practice activities for students to try. The answers for each question are listed in the final pages of the book. The middle section feels like the heaviest part of the whole book--it would take the longest time for a student to digest if assigned the whole chapter. Even though this middle section is a bit heavy, it does fit the overall structure and flow of the book. New material builds on previous chapters and sub-chapters. It ends abruptly--I didn't realize that it had ended, and all of a sudden I found myself in the answer section for those earlier exercises.

The simple layout is quite helpful! There is nothing distracting, image-wise, in this text. The table of contents is clearly arranged, and each topic is easy to find.

Tiny edits could be made (Starbuck's/Starbucks, for one). Otherwise, it is free of distracting grammatical errors.

This text is quite culturally relevant. For instance, there is one example that mentions the rumors of Barack Obama's birthplace as somewhere other than the United States. This example is used to explain how to analyze an argument for validity. The more "sensational" examples (like the Obama one above) are helpful in showing argument structure, and they can also help students see how rumors like this might gain traction--as well as help to show students how to debunk them with their newfound understanding of argument and logic.

The writing style is excellent for the subject matter, especially in the third section explaining logical fallacies. Thank you for the opportunity to read and review this text!

Reviewed by Laurel Panser, Instructor, Riverland Community College on 6/20/17

This is a review of Introduction to Logic and Critical Thinking, an open source book version 1.4 by Matthew Van Cleave. The comparison book used was Patrick J. Hurley’s A Concise Introduction to Logic 12th Edition published by Cengage as well as... read more

This is a review of Introduction to Logic and Critical Thinking, an open source book version 1.4 by Matthew Van Cleave. The comparison book used was Patrick J. Hurley’s A Concise Introduction to Logic 12th Edition published by Cengage as well as the 13th edition with the same title. Lori Watson is the second author on the 13th edition.

Competing with Hurley is difficult with respect to comprehensiveness. For example, Van Cleave’s book is comprehensive to the extent that it probably covers at least two-thirds or more of what is dealt with in most introductory, one-semester logic courses. Van Cleave’s chapter 1 provides an overview of argumentation including discerning non-arguments from arguments, premises versus conclusions, deductive from inductive arguments, validity, soundness and more. Much of Van Cleave’s chapter 1 parallel’s Hurley’s chapter 1. Hurley’s chapter 3 regarding informal fallacies is comprehensive while Van Cleave’s chapter 4 on this topic is less extensive. Categorical propositions are a topic in Van Cleave’s chapter 2; Hurley’s chapters 4 and 5 provide more instruction on this, however. Propositional logic is another topic in Van Cleave’s chapter 2; Hurley’s chapters 6 and 7 provide more information on this, though. Van Cleave did discuss messy issues of language meaning briefly in his chapter 1; that is the topic of Hurley’s chapter 2.

Van Cleave’s book includes exercises with answers and an index. A glossary was not included.

Reviews of open source textbooks typically include criteria besides comprehensiveness. These include comments on accuracy of the information, whether the book will become obsolete soon, jargon-free clarity to the extent that is possible, organization, navigation ease, freedom from grammar errors and cultural relevance; Van Cleave’s book is fine in all of these areas. Further criteria for open source books includes modularity and consistency of terminology. Modularity is defined as including blocks of learning material that are easy to assign to students. Hurley’s book has a greater degree of modularity than Van Cleave’s textbook. The prose Van Cleave used is consistent.

Van Cleave’s book will not become obsolete soon.

Van Cleave’s book has accessible prose.

Van Cleave used terminology consistently.

Van Cleave’s book has a reasonable degree of modularity.

Van Cleave’s book is organized. The structure and flow of his book is fine.

Problems with navigation are not present.

Grammar problems were not present.

Van Cleave’s book is culturally relevant.

Van Cleave’s book is appropriate for some first semester logic courses.

Table of Contents

Chapter 1: Reconstructing and analyzing arguments

• 1.1 What is an argument?
• 1.2 Identifying arguments
• 1.3 Arguments vs. explanations
• 1.4 More complex argument structures
• 1.5 Using your own paraphrases of premises and conclusions to reconstruct arguments in standard form
• 1.6 Validity
• 1.7 Soundness
• 1.8 Deductive vs. inductive arguments
• 1.9 Arguments with missing premises
• 1.10 Assuring, guarding, and discounting
• 1.11 Evaluative language
• 1.12 Evaluating a real-life argument

Chapter 2: Formal methods of evaluating arguments

• 2.1 What is a formal method of evaluation and why do we need them?
• 2.2 Propositional logic and the four basic truth functional connectives
• 2.3 Negation and disjunction
• 2.4 Using parentheses to translate complex sentences
• 2.5 “Not both” and “neither nor”
• 2.6 The truth table test of validity
• 2.7 Conditionals
• 2.8 “Unless”
• 2.9 Material equivalence
• 2.10 Tautologies, contradictions, and contingent statements
• 2.11 Proofs and the 8 valid forms of inference
• 2.12 How to construct proofs
• 2.13 Short review of propositional logic
• 2.14 Categorical logic
• 2.15 The Venn test of validity for immediate categorical inferences
• 2.16 Universal statements and existential commitment
• 2.17 Venn validity for categorical syllogisms

Chapter 3: Evaluating inductive arguments and probabilistic and statistical fallacies

• 3.1 Inductive arguments and statistical generalizations
• 3.2 Inference to the best explanation and the seven explanatory virtues
• 3.3 Analogical arguments
• 3.4 Causal arguments
• 3.5 Probability
• 3.6 The conjunction fallacy
• 3.7 The base rate fallacy
• 3.8 The small numbers fallacy
• 3.9 Regression to the mean fallacy
• 3.10 Gambler's fallacy

Chapter 4: Informal fallacies

• 4.1 Formal vs. informal fallacies
• 4.1.1 Composition fallacy
• 4.1.2 Division fallacy
• 4.1.3 Begging the question fallacy
• 4.1.4 False dichotomy
• 4.1.5 Equivocation
• 4.2 Slippery slope fallacies
• 4.2.1 Conceptual slippery slope
• 4.2.2 Causal slippery slope
• 4.3 Fallacies of relevance
• 4.3.1 Ad hominem
• 4.3.2 Straw man
• 4.3.3 Tu quoque
• 4.3.4 Genetic
• 4.3.5 Appeal to consequences
• 4.3.6 Appeal to authority

Answers to exercises Glossary/Index

Ancillary Material

About the book.

This is an introductory textbook in logic and critical thinking. The goal of the textbook is to provide the reader with a set of tools and skills that will enable them to identify and evaluate arguments. The book is intended for an introductory course that covers both formal and informal logic. As such, it is not a formal logic textbook, but is closer to what one would find marketed as a “critical thinking textbook.”

About the Contributors

Matthew Van Cleave ,   PhD, Philosophy, University of Cincinnati, 2007.  VAP at Concordia College (Moorhead), 2008-2012.  Assistant Professor at Lansing Community College, 2012-2016. Professor at Lansing Community College, 2016-

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Freshman course logic and critical thinking

2021, Ethiopian freshman course logic course

FEDERAL DEMOCRATIC REPUBLIC OF ETHIOPIA MINISTRY OF SCIENCE AND HIGHER EDUCATION LOGIC AND CRITICAL THINKING COURSE CODE: PHIL 1011

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Louise Cummings

Dr. S. Lourdu nathan

Rhetoric and Argumentation in the Beginning of the XXIst Century, ed Henrique Jales Ribeiro,University of Coimbra Press, Coimbra, Portugal, 2009, 87-109.

Matheus Silva

Macagno, F. & Walton, D. (2017). Interpreting Straw Man Argumentation. The pragmatics of Quotation and Reporting. Amsterdam: Springer. ISBN: 978-3-319-62544-7.

FABRIZIO MACAGNO , Douglas Walton

Juho Ritola

International Commentary on Evidence

Tamkeen Shah

Open textbook

Matthew Van Cleave

Rethinking the BSE Crisis

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PHIL102: Introduction to Critical Thinking and Logic

Course introduction.

• Time: 40 hours
• College Credit Recommended ($25 Proctor Fee) -->
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The course touches upon a wide range of reasoning skills, from verbal argument analysis to formal logic, visual and statistical reasoning, scientific methodology, and creative thinking. Mastering these skills will help you become a more perceptive reader and listener, a more persuasive writer and presenter, and a more effective researcher and scientist.

The first unit introduces the terrain of critical thinking and covers the basics of meaning analysis, while the second unit provides a primer for analyzing arguments. All of the material in these first units will be built upon in subsequent units, which cover informal and formal logic, Venn diagrams, scientific reasoning, and strategic and creative thinking.

Course Syllabus

First, read the course syllabus. Then, enroll in the course by clicking "Enroll me". Click Unit 1 to read its introduction and learning outcomes. You will then see the learning materials and instructions on how to use them.

Unit 1: Introduction and Meaning Analysis

Critical thinking is a broad classification for a diverse array of reasoning techniques. In general, critical thinking works by breaking arguments and claims down to their basic underlying structure so we can see them clearly and determine whether they are rational. The idea is to help us do a better job of understanding and evaluating what we read, what we hear, and what we write and say.

In this unit, we will define the broad contours of critical thinking and learn why it is a valuable and useful object of study. We will also introduce the fundamentals of meaning analysis: the difference between literal meaning and implication, the principles of definition, how to identify when a disagreement is merely verbal, the distinction between necessary and sufficient conditions, and problems with the imprecision of ordinary language.

Completing this unit should take you approximately 5 hours.

Unit 2: Argument Analysis

Arguments are the fundamental components of all rational discourse: nearly everything we read and write, like scientific reports, newspaper columns, and personal letters, as well as most of our verbal conversations, contain arguments. Picking the arguments out from the rest of our often convoluted discourse can be difficult. Once we have identified an argument, we still need to determine whether or not it is sound. Luckily, arguments obey a set of formal rules that we can use to determine whether they are good or bad.

In this unit, you will learn how to identify arguments, what makes an argument sound as opposed to unsound or merely valid, the difference between deductive and inductive reasoning, and how to map arguments to reveal their structure.

Completing this unit should take you approximately 7 hours.

Unit 3: Basic Sentential Logic

This unit introduces a topic that many students find intimidating: formal logic. Although it sounds difficult and complicated, formal (or symbolic) logic is actually a fairly straightforward way of revealing the structure of reasoning. By translating arguments into symbols, you can more readily see what is right and wrong with them and learn how to formulate better arguments. Advanced courses in formal logic focus on using rules of inference to construct elaborate proofs. Using these techniques, you can solve many complicated problems simply by manipulating symbols on the page. In this course, however, you will only be looking at the most basic properties of a system of logic. In this unit, you will learn how to turn phrases in ordinary language into well-formed formulas, draw truth tables for formulas, and evaluate arguments using those truth tables.

Completing this unit should take you approximately 13 hours.

Unit 4: Venn Diagrams

In addition to using predicate logic, the limitations of sentential logic can also be overcome by using Venn diagrams to illustrate statements and arguments. Statements that include general words like "some" or "few" as well as absolute words like "every" and "all" – so-called categorical statements – lend themselves to being represented on paper as circles that may or may not overlap.

Venn diagrams are especially helpful when dealing with logical arguments called syllogisms. Syllogisms are a special type of three-step argument with two premises and a conclusion, which involve quantifying terms. In this unit, you will learn the basic principles of Venn diagrams, how to use them to represent statements, and how to use them to evaluate arguments.

Completing this unit should take you approximately 6 hours.

Unit 5: Fallacies

Now that you have studied the necessary structure of a good argument and can represent its structure visually, you might think it would be simple to pick out bad arguments. However, identifying bad arguments can be very tricky in practice. Very often, what at first appears to be ironclad reasoning turns out to contain one or more subtle errors.

Fortunately, there are many easily identifiable fallacies (mistakes of reasoning) that you can learn to recognize by their structure or content. In this unit, you will learn about the nature of fallacies, look at a couple of different ways of classifying them, and spend some time dealing with the most common fallacies in detail.

Completing this unit should take you approximately 3 hours.

Unit 6: Scientific Reasoning

Unlike the syllogistic arguments you explored in the last unit, which are a form of deductive argument, scientific reasoning is empirical. This means that it depends on observation and evidence, not logical principles. Although some principles of deductive reasoning do apply in science, such as the principle of contradiction, scientific arguments are often inductive. For this reason, science often deals with confirmation and disconfirmation.

Nonetheless, there are general guidelines about what constitutes good scientific reasoning, and scientists are trained to be critical of their inferences and those of others in the scientific community. In this unit, you will investigate some standard methods of scientific reasoning, some principles of confirmation and disconfirmation, and some techniques for identifying and reasoning about causation.

Completing this unit should take you approximately 4 hours.

Unit 7: Strategic Reasoning and Creativity

While most of this course has focused on the types of reasoning necessary to critique and evaluate existing knowledge or to extend our knowledge following correct procedures and rules, an enormous branch of our reasoning practice runs in the opposite direction. Strategic reasoning, problem-solving, and creative thinking all rely on an ineffable component of novelty supplied by the thinker.

Despite their seemingly mystical nature, problem-solving and creative thinking are best approached by following tried and tested procedures that prompt our cognitive faculties to produce new ideas and solutions by extending our existing knowledge. In this unit, you will investigate problem-solving techniques, representing complex problems visually, making decisions in risky and uncertain scenarios, and creative thinking in general.

Completing this unit should take you approximately 2 hours.

Study Guide

This study guide will help you get ready for the final exam. It discusses the key topics in each unit, walks through the learning outcomes, and lists important vocabulary terms. It is not meant to replace the course materials!

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If you come across any urgent problems, email [email protected].

Certificate Final Exam

Take this exam if you want to earn a free Course Completion Certificate.

To receive a free Course Completion Certificate, you will need to earn a grade of 70% or higher on this final exam. Your grade for the exam will be calculated as soon as you complete it. If you do not pass the exam on your first try, you can take it again as many times as you want, with a 7-day waiting period between each attempt.

Once you pass this final exam, you will be awarded a free Course Completion Certificate .

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Take this exam if you want to earn college credit for this course . This course is eligible for college credit through Saylor Academy's Saylor Direct Credit Program .

The Saylor Direct Credit Final Exam requires a proctoring fee of $5 . To pass this course and earn a Credly Badge and official transcript , you will need to earn a grade of 70% or higher on the Saylor Direct Credit Final Exam. Your grade for this exam will be calculated as soon as you complete it. If you do not pass the exam on your first try, you can take it again a maximum of 3 times , with a 14-day waiting period between each attempt.

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Introduction to Logic and Critical Thinking

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1.1: Vital Course Concepts

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Have you ever been in a conversation with someone and found that they were mischaracterizing what you were saying, bombarding you with seemingly unrelated information, giving up on reasoning at all and instead simply blustering? It feels like you want to figure out what is true and really try to understand the issue you’re discussing, but the person you’re talking to just wants to make some talking points or get a few shots in before plugging their ears and singing to themselves. Like having the discussion, to them, is just a game that they want to win at any cost. I’ve been there, loads of times. Not fun.

Rhetoric vs. Reasoning

In ancient Greece one of the most famous Western philosophers of all time—Socrates—noticed that there were different ways that people came to believe what they believe.

• Some people listened to the poets, the oracles, the playwrights, etc. for truth. They looked to Tradition to find out what they should believe, how they should act, what reality was like, etc. Think Homer: they read the Iliad and the Odyssey and took life lessons from its pages.
• Others found that by manipulating those around them they could come to win arguments reliably. They found that discussions were sort of like jousting matches in that the person who won the argument was usually the person who was the quickest wit and had the best tools at their disposal. They didn’t care about what was true, or good, or right. They only cared about winning and about Rhetoric . They were the lawyers and politicians of their day (not to say that there aren’t good, honest, principled lawyers and politicians). They were called Sophists .
• Socrates himself preferred a different route he called Dialectic , where a person made a claim and then others asked critical questions about their claim or position until they found themselves confused and unsure of what to believe. This process of breaking down our presuppositions helped us move past false confidence . The closer we move toward what was called aporia —a state of “impasse” where we’re not sure which direction to take—the more we’re able to consider what the truth is about from all of the baggage we carry from our childhood, from previous conversations, from popular media, etc.

Sophists are interested in good rhetoric . Good rhetoric is important. In fact, we have whole courses and sometimes whole departments devoted to good rhetoric. We need to find ways of expressing our ideas in a way that gets the right reaction from our intended audiences.

Philosophers, like Socrates, are interested in good reasoning or argumentation . We philosophers (and I count myself among them) care about rhetoric only to the extent that we’re not misleading our audiences or turning them off of our position without good reason. We want to explore what the best reasons are for accepting or rejecting different positions. We don’t want to win an argument if we’re wrong. We’re ready and willing to revise our beliefs if we find out that we don’t have good reason for accepting them.

With this in mind, we can posit a distinction between rhetoric and reasoning. Two things you’ll be worried about to different degrees in different situations. Sometimes you’ll care a lot about how your audience will receive your arguments and other times you’ll care more about simply getting it right.

Rhetoric : Is primarily concerned with the impact of an argument or piece of writing or speech or the like. How effectively is it producing the effect I want in my audience?

Reasoning : is concerned with insight, discovery, truth, and understanding. The goal isn’t to produce a certain impact in the audience, but instead to collectively discover what the best position on a given question is or what the objective merits and demerits of an argument or position are.

This is a course about argumentation and reasoning, we’ll be interested in Rhetoric only insofar as it gets in the way of good, honest, clear argumentation. (That isn’t to say that rhetoric always gets in the way. Sometimes, in fact, good rhetoric can amplify good reasoning. Good reasoning is dry and inaccessible without good rhetoric!)

Propositions

So we’re interested in how arguments work. What makes them tick? What makes the good ones good and the bad ones bad? How can I make a series of statements and then think that I’ve “proven” or “demonstrated” a further statement? In order to understand arguments, we’ll have to start with the fundamental building blocks: propositions or statements:

Definition: Propositions

Propositions are statements that can be true or false. This is the fundamental concept of the course. Take the time to understand it clearly.

If a statement can be true or false, then it’s a proposition. Note that a sentence and a proposition aren’t the same thing. Not all sentences are propositions.

When we reason, we make statements or consider statements and then we back those statements up with reasons and evidence, draw out the implications and consequences of those statements and so on. There’s a technical distinction between a statement and a proposition, but we will use them interchangeably here. For our purposes, a statement and a proposition are the same thing.

Some sentences don’t express propositions at all. This means that they can’t be true or false. You can’t disagree with them, you can’t argue about whether they’re right or wrong, you can’t question them. Not because they’re indubitable (un-doubt-able), but simply because it wouldn’t make any sense to disagree with them!

If I said, “Can we please go out to dinner tonight?” you can’t respond with disagreement, saying “I don’t know about that claim, it doesn’t sound right to me.” I haven’t made a statement, so you can’t say I’ve stated something false. Similarly, if you say “wash your hands before dinner” I can’t respond with “that’s false.” It wouldn’t make any sense. These types of sentences don’t express propositions. They’re non-propositions.

Definition: Non-Propositions

Sentences that aren’t statements about matters of fact (or fiction). They don’t make a claim that can be true or false. They:

• Exhort : Let’s go get drinks! Let us go hiking on Tuesday!
• Command : Go to the store later to buy me some cheese. Don’t do that.
• Plead/Request : Would you please stop that? Please read me a bedtime story!
• Question : What is the capital of the UAE? How much do the pineapples cost?
• Perform : I hereby adjourn this meeting! I pronounce you husband and wife!

Complex Propositions

Okay, back to propositions. Sometimes propositions are simple, and sometimes they are complex. Meaning sometimes they can be broken down into simpler propositions and sometimes they’re already as simple as they could be.

Definition: Simple Propositions

Simple Propositions have no internal logical structure , meaning whether they are true or false doesn’t depend on whether a part of them is true or false. They are simply true or false on their own.

• The GDP of the United States is $5.
• The Sky is Blue.
• Freedom should be the highest value of the state for its citizens.
• Harry Potter wears glasses.

Definition: Complex Propositions

Complex Propositions have internal logical structure, meaning they are composed of simple propositions. Whether they are true or false depends on whether their parts are true or false.

• The GDP of the United States is either $5 or it is $12.
• True if the GDP is $5 or if the GDP is $12
• The Sky is Blue, but it doesn’t look blue to me right now.
• True if the Sky is blue and if it doesn’t look blue to me right now .
• If freedom should be the highest value of the state for its citizens , then we should promote it in our laws and policies.
• True if it can’t be that “ freedom should be the highest value of the state for its citizens ” is true while “ we should promote freedom in our laws and policies ” is false.

In short, each proposition is either a simple proposition or a combination of simple propositions. Simple propositions are true or false just based on how the world is, whereas complex propositions are true or false just based on whether or not the simple propositions that make them up are true or false.

I am an elephant

...is a false proposition if I say or think it. It’s false because of the way the world is—I am not in fact an elephant.

I am an elephant or I am a human

...is a true complex proposition if I say or think it. The way “or” propositions work is that only one of the simple propositions needs to be true. The left proposition “I am an elephant” is false, but the right one “I am a human” is true. So, since complex propositions depend on their parts for their truth values, the complex proposition as a whole is true!

We can learn to break propositions down into parts. This is an important skill to grasp so that you can understand all of the separate claims someone is making in a single sentence. People often make a host of claims in a single sentence, and you’ll want to be able to separate them.

Breaking down complex propositions usually involves identifying the little sentences that make up a complex sentence. So instead of saying “Bobby doesn’t want to play basketball, but he does want to play videogames.” I notice that the “but” connects two independent thought: Bobby doesn’t want to play basketball. Bobby wants to play videogames.

“Either you know everything there is to know, or I’m a monkey’s uncle and you’re not as smart as I thought you were.” Breaks down into three separate propositions since there’s an “either...or...” and also an “and”.

Breaking down Propositions : separate out the statements that can be independently true or false. It’s a bit tricky and interpretive, but we’re just trying to grasp the basic concept here.

We’ll get into this more later in the course, but for now it’s good to have some facility with the basic idea: some propositions don’t have parts that can be true or false independently, while others do. We use words like ‘and’, ‘or’, ‘Either...or...’, ‘but’, and ‘if...then...’ to identify multiple independent propositions.

Example \(\PageIndex{1}\)

• Marcos is taking four courses this semester.
• Marcos is working in his parents’ store 20 hour a week this semester.
• Frankie went to dinner.
• Johnny went to dinner.
• Luigi went to dinner.
• Karen is smart
• Karen is not very motivated to do well in school.
• Karen is not very motivated to try to find a job that uses her talents.

Okay, so now we know that there’s an important difference between sentences which express propositions and those that do not. We also know that some sentences express multiple simple propositions and some express only one simple proposition. We’ve hopefully got a good grasp on what a proposition is at this point.

Inferences or Arguments

The topic of the course is the argument or inference . What’s that?

Definition: Inference or Argument

An Inference or Argument is any purportedly rational movement from evidence or premises to a conclusion.

Any time you’re being asked to accept one claim on the basis of or because of any number of other claims, you’ve got an inference/argument. “I believe x, because of y, z, and w” or “Because a, b and c, we have to believe that d.”

The following is from Knachel, Fundamental Methods of Logic, CC-BY 4.0 Int’l

If we’re reasoning by making claims and backing them up with reasons, then the claim that’s being backed up is the conclusion of an argument; the reasons given to support it are the argument’s premises. If we’re reasoning by drawing an inference from a set of statements, then the inference we draw is the conclusion of an argument, and the statements from which its drawn are the premises.

We include the parenthetical hedge—“supposed to be”—in the definition to make room for bad arguments. Remember, in Logic, we’re evaluating reasoning. Arguments can be good or bad, logically correct or incorrect. A bad argument, very roughly speaking, is one where the premises fail to support the conclusion; a good argument’s premises actually do support the conclusion.

To support the conclusion means, again very roughly, to give one good reasons for believing it. This highlights the rhetorical purpose of arguments: we use arguments when we’re disputing controversial issues; they aim to persuade people, to convince them to believe their conclusion. 3 As we said, in logic, we don’t judge arguments based on whether or not they succeed in this goal—there are logically bad arguments that are nevertheless quite persuasive. Rather, the logical enterprise is to identify the kinds of reasons that ought to be persuasive (even if they sometimes aren’t).

So you’ve got some support for a conclusion and then that conclusion. The relationship between that support and that conclusion is supposed to be rational —we’re supposed to believe that the support we’re given proves or demonstrates or gives us reason to believe the conclusion.

Less abstractly, here’s an example:

Example \(\PageIndex{2}\)

Bob Marley wrote “One Love”

Bob Marley sang the best rendition of “Don’t Worry, Be Happy”

Bob Marley wrote “Three Little Birds”

Bob Marley wrote “No Woman No Cry”

Bob Marley wrote “Buffalo Soldier”

So Bob Marley is the greatest musician of all time

We’re being asked to believe a number of things here. First, we’re supposed to believe that Marley wrote each of these songs. We’re also being asked to believe that his version of “Don’t Worry, Be Happy” is the best version ever. Finally, and most importantly, we’re being asked to believe that because all of these things are true, it follows that Bob Marley is the greatest musician of all time.

This isn’t a very good argument. It’s not being very good has nothing to do with the conclusion . I love Bob Marley and I do think he has written some of the best songs of all time, but I don’t think that these premises entail this conclusion. That is, even if we accept all of these premise, we need not accept the conclusion. “Oh yeah?” someone can reasonably reply, “those are all amazing songs, yes. And I don’t dispute that Marley wrote them, but none of them is as good as Bohemian Rhapsody. Queen is therefore better and Bob Marley cannot be the greatest musician of all time.” There’s no inconsistency with believing that this argument uses good premises to support a possibly-true conclusion, but doesn’t really demonstrate that conclusion using those premise. We can believe the conclusion is true without accepting that the argument supports the conclusion.

Premises and Conclusions

All arguments have a common anatomy:

There may be many premises, but they’re all supposed to be statements (propositions) which support or demonstrate the conclusion—whether directly or indirectly. A premise is a proposition which lends credence to the conclusion. It’s supposed to be a group of statements that, if you accept that they’re true, make it the case that you rationally must ( or, weaker, should) accept the conclusion. That’s not the case above in our Bob Marley argument. Here’s an argument where it is true:

All Roses are Red

All Red Things are Ugly

All Roses are Ugly

If it is in fact true that all roses are red and if it is in fact true that all red things are ugly, then it follows with absolute certainty that all roses are ugly. Try to accept the premises and reject the conclusion. Can’t do it. It’s impossible.

According to the first premise, all of the roses are red things. Notice how all of the roses fit inside all of the red things? That’s a graphical way of representing the claim that there are no roses outside of the category of red things. If you’re looking for a rose, you’re looking for a red thing. No non-red roses. All roses are red.

According to the second premise, all of the red things are ugly things. See how they all fit inside the circle? Well, if the roses are in the red things circle and the red things circle is in the ugly things circle, it follows that the roses circle is in the ugly things circle. That make sense?

Notice how we probably don’t want to accept the conclusion here. Most of us are on board with roses. We think that roses are beautiful or at least that they’re not ugly. So we don’t like this argument. But we can’t, when rejecting an argument, reject the conclusion directly. Why? Well, because the premises are supposed to be proving the conclusion. If the premises are true, then the conclusion must be true. We have to, therefore, reject one of the premises here. The second premise is clearly false. There are lots of pretty and red things. Red roses for instance. Furthermore, not all roses are red! The two premises were false in this case. If, however, you thought both premises were true, you’d have to accept the conclusion as well.

Imagine your two friends are dating. If you want to invite one of them to hang out in a group setting, both of them will generally want to come. All of a sudden, they’re a package deal, right?

They have a relationship with one another such that if you take one, you have to take the other as well. That’s sort of how premises and conclusions work. They have a logical relationship with one another such that if you think the premises are true, you must also think that the conclusion is true. They’re a package deal.

The previous argument illustrates the point that arguments sometimes are bad . There are sometimes reasons to reject an argument (mind you, not to decide that its conclusion is false, but instead to decide that it didn’t demonstrate its conclusion).

Arguments can go wrong in only two ways:

1. Bad Inferential Structure : every argument with the same structure as this argument is bad (invalid or weak). The premises don’t in fact demonstrate or maybe even support the conclusion. In other words: we can accept the premises as true without being compelled to accept the conclusion. There’s something wrong with this argument’s general structure.

2. False Premise(s) : this particular argument has a premise/assumption that is false. There’s something wrong with this argument’s particular content.

The following is from Matthew J. Van Cleave’s Introduction to Logic and Critical Thinking , version 1.4, pp. 2-3. Creative Commons Attribution 4.0 International License.

So, to reiterate: all arguments are composed of premises and conclusions, which are both types of statements. The premises of the argument provide a reason for thinking that the conclusion is true. And arguments typically involve more than one premise. A standard way of capturing the structure of an argument is by numbering the premises and conclusion. For example, recall Sally’s argument against abortion:

Example \(\PageIndex{3}\)

Abortion is morally wrong because it is wrong to take the life of an innocent human being, and a fetus is an innocent human being.

We could capture the structure of that argument like this:

1. It is morally wrong to take the life of an innocent human being

2. A fetus is an innocent human being

3. Therefore, abortion is morally wrong

By convention, the last numbered statement (also denoted by the “therefore”) is the conclusion and the earlier numbered statements are the premises. This is what we call putting an argument into standard argument form. We can now give a more precise definition of an argument. An argument is a set of statements, some of which (the premises) attempt to provide a reason for thinking that some other statement (the conclusion) is true. Although arguments are typically given in order to convince or persuade someone of the conclusion, the argument itself is independent of one’s attempt to use it to convince or persuade. For example, I have just given you this argument not in an attempt to convince you that abortion is morally wrong, but as an illustration of what an argument is. Later on in this chapter and in this book we will learn some techniques of evaluating arguments, but for now the goal is to learn to identify an argument, including its premises and conclusion(s). It is important to be able to identify arguments and understand their structure, whether or not you agree with conclusion of the argument.

How do we identify Premises and Conclusions? Good question! First, we can sometimes identify premises and conclusions simply by recognizing the role they play in an argument. Here’s an argument, for example:

Example \(\PageIndex{4}\)

Migratory butterflies are facing strain or possible extinction due to the overdevelopment of lands along their migration routes. In developing the routes, humans have tended to remove milkweed, which is a central food source for migratory butterflies.

There are two claims here. One seems to support the other one and not the other way around. Which one seems like the claim being supported here? Which one seems like it’s doing the supporting? Good! Right-o, chum. See how the first sentence raises a question and the second sentence answers it? “What’s the relationship between developing land and migratory butterflies?” or simply “Why should we believe that?” The second question answers these questions: we should believe the first sentence because developing means removing milkweed, which is a food source for butterflies.

Second, we can recognize conclusions and premises by identifying certain words being used: these are called conclusion indicators and premise indicators . If one of these words is used, typically that means that you’ve spotted a conclusion or a premise (depending on the indicator).

Conclusion Indicators all have the general sense of “I’ve told you some things or I’m about to tell you some things, now here’s what I want you to believe.” They have a conclusive feel to them. Here are some especially common ones:

Premise indicators, on the other hand, have the general sense of “from this fact I’m going to infer something else”. Here are some common premise indicators:

Here’s an example argument that I’ve packed with Indicators:

Example \(\PageIndex{5}\)

In that the legislature has not approved it, and given that it is unconstitutional for me to do it on my own, I must conclude that there is no legal way for me to complete the project using only executive orders and the budgetary authority given to the executive branch. Furthermore, as indicated by the general lack of public support for the plan, it follows that I will be acting in line with the popular will on this issue. Therefore, I must not allocate money to make Fridays “free pizza days” since to do so would be a great abuse of executive power.

Factual Claims and Inferential Claims

Each argument makes two different sorts of claims, as we saw with the Bob Marley example above. There are a number of independent factual claims: claims about what is in fact the case or about what the world is like. There is also a somewhat hidden claim that the premises presented compel us to accept the conclusion presented—that there’s a good inference from these premises to that conclusion.

Facts and Inferences

argument makes two sets of claims:

• The Factual claims are in the premises: the arguer is claiming that all of the premises are true.
• The Inferential claim is often implied. The arguer is also claiming that the premises give conclusive support to the conclusion.

Remember that these are the two ways an argument can break down : it can make a false factual claim (a premise can be false) or its premises can fail to support its conclusion (the implicit inferential claim can be false).

So since we couldn’t possibly find an argument with the same general structure as the previous argument that has true premises, but a false conclusion, we conclude that the structure of that argument was deductively valid. We went through the steps to show that the argument is valid. We demonstrated it with the circles above (these are called “Euler [1] Diagrams”). Here’s the structure without the particular content:

All \(\Omega\)s are \(\Delta\)s

All \(\Delta\)s are \(\Psi\)s

All \(\Omega\)s are \(\Psi\)s

So now we have the same types of propositions in the same order, but we’re no longer just talking about roses and red things and ugly things. Any argument with this form will be valid: you won’t be able to reject the conclusion if you accept the premises. This is what it means to have good inferential structure if you’re a deductive argument. We’ll get into the difference between deductive and inductive arguments later.

Here’s an invalid inferential structure:

All \(\Psi\)s are \(\Delta\)s

How do we know it’s invalid? Well, easy. We find an example of an argument with the same argument form such that the premises are true and the conclusion is false. How about this example?

Example \(\PageIndex{6}\)

All Guavas are Fruits

All Strawberries are Fruits

All Guavas are Strawberries

Guavas and Strawberries are two different sorts of fruit, but that doesn’t mean that they’re the same thing!

Let’s check out what the Euler Diagram looks like:

See how strawberries and guavas don’t need to overlap at all to make the premises true? But the conclusion says that they totally overlap . So the premises do not entail the conclusion. We can accept the premises without accepting the conclusion. We only need this one counterexample to show that this argument structure is invalid.

What does it mean to have a false premise? Pretty simple. Each premise makes a statement about how the world is. The world either is or isn’t that way, so each premise either is or isn’t true. Any argument with a false premise isn’t a good argument. All of the premises must be true for an argument to have successfully demonstrated its conclusion.

Definition: Parts of any argument

The Conclusion is the claim that the whole argument is intended to support or demonstrate or prove. It’s the reason we make an argument: to support or demonstrate the conclusion.

The Premises are the claims, evidence, ideas, etc. that are intended to support the conclusion

• They are the assumptions we are asked to take on board. If they are true, then the conclusion either must be or is likely true as well.

Here’s a heuristic or rough rule that can sometimes help you identify premises and conclusions. If you are told a premise, you’ll likely not understand why you were told it until you see that it fits into an argument. If you are told a conclusion, you’ll likely wonder what reason the person has for thinking it’s true. The conclusion is the “point” of bringing up the premises: to demonstrate that the conclusion is true. The premises are reasons we have for believing the conclusion.

The following section was written by Michael Fitzpatrick

A guiding assumption of this textbook is that truth is our aim when evaluating particular arguments and their conclusions. But what is truth, and why is it so important? After all, many people today seem to think that truth is just whatever a person believes, or that truth doesn’t matter as much as other values such as economic success, political pragmatism, or self-fulfillment. Contrary to these trends, this textbook affirms that thinking well flows out of the nature and value of truth, and that the value of truth should guide how we think.

The name ‘truth’ gathers together our human concerns about accuracy and sincerity, to use the two underlying notions proposed by Bernard Williams in his book Truth and Truthfulness . When asserting propositions, adopting beliefs, creating blueprints, drawing maps, giving directions, following cooking recipes, or even just trying to see how much taller a teenager on a growth spurt is since last year, what we’re aiming at is an accurate understanding of our world and our projects in the world. Accuracy is a more or less concept, one we apply for instance in the game of darts. When throwing at a dart board, we aim for the bull’s-eye, and we are more or less accurate depending on how close we get to the target. But truth is not simply about accuracy; it also concerns sincerity, that dimension of representing ourselves and others and our world in ways that are genuine, faithful, trustworthy, and can be taken as presented. When we ask a friend for directions to the gas station, we’re not just depending on the accuracy of their instructions, but also their sincerity in not wanting to deceive us and in wanting to be someone who is trustworthy.

Truth understood as the interplay of accuracy and sincerity describes a fundamental way human beings exist. To interact truthfully in the world is to experience ourselves, our neighbors, and our environment as it really is, not as we wish it to be. The mode of truth highlights our capacity to receive new information from sources other than ourselves.

Truth is, as Martin Heidegger suggests, “uncovering,” the unconcealing of what is with us in the world, seen for its own sake. In his book Kant and the Platypus , Umberto Eco suggests that truth involves our encounter with “lines of resistance” in the world, ways in which reality pushes back against our concepts and perceptions. In a particularly pregnant passage, Eco describes reality as a continuum with definite shape,

As if to say that in the magma of the continuum there are lines of resistance and possibilities of flow, as in the grain of wood or marble, which make it easier to cut in one direction than in another. It is like beef or veal: in different cultures the cuts vary, and so the names of certain dishes are not always easy to translate from one language to another. And yet it would be very difficult to conceive of a cut that offered at the same moment the tip of the nose and the tail.

If the continuum has a grain, unexpected and mysterious as it may be, then we cannot say all we want to say. Being may not be comparable to a one-way street but to a network of multilane freeways along which one can travel in more than one direction; but despite this some roads will nevertheless remain dead ends. There are things that cannot be done (or said). (53)

Truth names the lines of resistance contouring what we can say, believe, do, experience, and imagine. Resistance does not entail impossibility; we are capable of astonishing creativity that can be used to distort reality, whether by lying to others, creating elaborate conspiracy theories, or engaging in our own self-deception. The point is not that we cannot do these things, but that to do them we have to overcome the resistance of reality. When we are sincere people seeking to aim accurately, we are letting ourselves be shaped by the “frictions” we experience as beings in the world.

The foregoing portrait of truth helps to uncover the value truth has and its indispensable role in human life. Truth is both intrinsically and instrumentally valuable: something is intrinsically valuable when it is a end in itself, and instrumentally valuable when it is a means to a end. Truth, like justice and goodness, is both. Truth is also essential to other values humans hold, as well as to a healthy psychological life. We’ll cover each of these in turn.

1. Truth has intrinsic value because it satisfies our curiosity and wonder at existence. To be human is to explore and discover. We try to figure out how electrons can be both a wave and a particle; what creatures live in the darkest regions of the oceans; why whales are mammals that evolved back into the sea; and what the heck is a platypus anyway?! We even investigate the mystery of our selves—from our ingrained irrationality to our capacity for language to our religious tendencies to the enigma of consciousness, we humans want to understand who we are. As we explore our own identities and values, we discover what is true about us, which means we transcend our own fantasies, illusions, and folk stories about who we are.

2. Truth also has instrumental value for protecting ourselves against manipulation by other people. Consider this: you are not free to believe whatever you want. What I mean is, you can’t just will yourself to believe something. Try it – will yourself right now to believe that there is a pink elephant in the room with you. No matter how hard you try, you can’t just decide to believe it (at least not sincerely ; you could say you believe it and not mean it). But you can decide to get others to believe something that is false or dangerous. You can trick or manipulate them into believing falsehoods, as a practical joke or to take advantage of them. But if you can do this to others ... they can do it to you too. If our beliefs are not guided by what is true, then we are vulnerable to other people influencing our beliefs according to what they want us to believe. Politicians do it all the time.

3. Truth is essential to being a responsible, ethical human being. We are not just physical beings governed by the laws of physics; we have responsibilities to ourselves and others. We need to care for our younger siblings, pay our credit card bills on time, not cheat on our sweethearts, and stand up for those less fortunate than ourselves. But meeting these responsibilities requires a reasonably accurate portrait of the world. If we don’t know the truth about other people—their needs and their hopes and their fears—or the truth about the material situation we all find ourselves in, then we can’t meet our responsibilities. Knowing what my sister needs from me requires knowing my sister, knowing the truth not only about her needs but how best to meet them given the resources I have. Action presupposes truth.

4. Finally, truth is essential to a healthy human psychological life. Bernard Williams, in his essay “Deciding to believe,” describes a man who knows his son is dead but does not want to believe it. Suppose the man decides to undertake some act of self-deception so that he no longer believes his son is dead. The problem is that there are other true beliefs the man probably has about the world that imply his son is dead (for instance, that his son never sends letters or comes for a visit). Williams writes,

The man gets rid of this belief about his son, and then there is some belief which strongly implies that his son is dead, and that has to be got rid of. Then there is sanother belief which could lead his thoughts in the undesired direction, and that has to be got rid of. It might be that a project of this kind tended in the end to involve total destruction of the world of reality, to lead to paranoia. Perhaps this is one reason why we have a strongly internalised objection to it. If we are not going to destroy all the evidence—all consciousness of the evidence—we have to have a project for steering ourselves through the world so as to avoid the embarrassing evidence. That sort of project is the project of the man who is deceiving himself, and he must really know what is true; for if he did not really know what was true, he would not be able to steer around the contrary and conflicting evidence. (151, from Problems of the Self)

The attempt to deceive ourselves into believing one false belief seems to lead to a life of real paranoia and psychological breakdown, as well as the incoherence of needing to know what is true in order to avoid what is true. Of course, believing true beliefs can also lead to psychological upheaval. The realization that Nazi Germany had engaged in extensive crimes against humanity and undertook a holocaust against Jewish and disabled peoples was enormously difficult for many German citizens to accept, and required tremendous revision in their beliefs about themselves, their communities, and their cultural identity. Yet upheaval by true beliefs is externally motivated, coming not from an internal paranoia or avoidance of reality, but from the “lines of resistance” and “uncovering” of reality we described above on the nature of truth. However difficult those truths may be to accept, they are more likely to lead to psychological stability in the long-term than, say, a holocaust denier who has to spend the rest of their lives refuting evidence and testimony about what really happened.

There are more reasons beyond these to value the pursuit of truth, but hopefully this provides a sense of why this class is focused on how to reason as well as humanly possible so as to live along the grain of the universe.

The Principle of Charity

Okay, Andrew’s back. Now let’s talk about a really important habit to get into. A sort of norm for reasoning well:

Always interpret your opponent/interlocuter’s position or argument so as to make it as strong or defensible as possible.

There are three reasons for this: one having to do with our goals in having reasoned discussions; another having to do with simple strategy if you are indeed interested in winning a debate; and finally one moral reason for following the principle of charity.

If you’re interested not in winning , but in understanding , then of course it doesn’t help to argue against the weakest version of someone’s position or the weakest justification available for someone’s position. For instance, if you want to understand the moral issue of abortion, then arguing with someone who makes a super weak version of an argument for or against abortion rights won’t really help you understand the issues at play in the moral debate. You might win the debate on that day, but you won’t have understood the issue with any more clarity.

When you disarm your conversant by letting them know that you understand their position and why someone might believe it, you open the door to more honest and open dialogue that allows for more understanding of each other’s viewpoints.

Even if you are interested in winning and you just want the most effective strategy for winning a debate, the principle of charity is still your best bet. Here’s an example of what not to do:

Example \(\PageIndex{7}\)

My opponent has argued against the idea that immigration is a fundamental human right. She must mean that even amnesty-seekers don’t have the moral right to immigrate away from immediate threats to life and limb. That position is totally ridiculous.

This isn’t very interesting. When you’re arguing, you want your opponent to be the hardest version of themselves to critique so that when you do critique them, your critique is the most interesting critique available. Think about how much more interesting it is if someone actually bolsters their opponent’s position by providing justifications for their position and then showing that their position is still wrong. That’s the kind of debate take-down I want to see.

Example \(\PageIndex{8}\)

My opponent has argued against immigration as a fundamental human right by appeal to simple scarcity: there’s not enough to go around. This, I’m afraid is simply false. There is more than enough to go around if we’re willing to redistribute resources effectively. Nevermind that, though, since there’s a stronger justification for my opponent’s position: that states have the fundamental right of sovereignty, which includes controlling traffic across their borders. This, we might think, is essential to what it means to be a state. This is a very interesting argument, but it still fails to convince me. Even if states have a right to border regulation, it doesn’t follow that individual human beings don’t still have a right to immigrate to where the greatest promise of prosperity is.

Isn’t this interesting? Wouldn’t you rather be in dialogue with this person or listen to a debate they’re in than someone who only attacks the weakest interpretation of their opponent’s position?

You don’t want your critique to be against a straw figure version of their argument (the easiest-to-refute version) because all they have to do is revise their position slightly and they can side-step your critique. You’ve set them up to make your critique null and void by simply clarifying their position as the stronger version.

This is also a good principle for living your life. You want to always attribute the most virtuous intentions to others and to the actions of others. This makes us easier to be around, more fun to converse with, and more empathetic and understanding people. It’s therefore a moral imperative that we treat each other with charity. After all, don’t you want to be given the benefit of the doubt?

We want to interpret each other’s actions and arguments as being as rational as possible so that we are in the best standing rationally speaking. We want to attribute the best, most rational intentions allowable by our evidence to those around us so that if we have a problem with what they’re doing, we at least have given them the benefit of the doubt and are more likely to correctly characterize what they’re up to. We want to ascribe the most defensible and reasonable arguments and claims to people with whom we disagree because we certainly don’t want to spend our time critiquing an argument or position that isn’t theirs ! We want to focus our energy on the best position or argument they have available to them because we are interested in finding out what the best thing to believe is —what’s true. We aren’t interested in winning for the sake of winning.

[1] Pronounced “Oiler” because it’s German.

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LOGIC AND CRITICAL THINKING MODULE COURSE

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Logic and Critical Thinking

Jul 27, 2014

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Logic and Critical Thinking. CCC8001 2 nd Term 2013. introduction. Course Particulars. Instructor: Dr. Michael Johnson Office: Room HSH219, Ho Sin Hang Building Office Hours: Monday s 15:00 to 16:00 Email: [email protected] Office Telephone: 2616 7052.

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Logic and Critical Thinking CCC8001 2nd Term 2013

introduction

Course Particulars • Instructor: Dr. Michael Johnson • Office: Room HSH219, Ho Sin Hang Building • Office Hours: Mondays 15:00 to 16:00 • Email: [email protected] • Office Telephone: 2616 7052

Course Website Go to http://michaeljohnsonphilosophy.com/logic-and-critical-thinking-2013/ All of the powerpoint slides will be posted there, along with reading assignments and homework assignments.

Meeting Times Monday 13:30 to 14:50 Leung KauKui (LKK) G01 Thursday 13:30 to 14:50 LKK 107

Assessment • Attendance: 10%. • Four homework assignments, each worth 5% of the grade, for a total of 20%. • One in-class midterm on 11 March, worth 30%. • One cumulative final exam, worth 40%.

Attendance Attendance is required and accounts for 10% of your final grade. You cannot get an ‘A’ in this course if you do not attend classes. Every day you don’t attend, you lose 0.5 points off your final grade, up to a maximum of 10.

Final Exam The final exam will occur during the scheduled exam period (TBA). It will consist of multiple choice and short-answer questions. It is worth 40% of your final grade. More details will be announced as the date of the final approaches. There will be a review (2/5).

Important Note Students shall be aware of the University regulations about dishonest practice in course work and the possible consequences as stipulated in the Regulations Governing University Examinations.

What is Critical Thinking? There are two basic decisions to make in life: 1. Decide what to believe: What do I believe? 2. Decide what to do: What do I do?

Deciding What to Believe The things you believe (or disbelieve) are claims. Examples of claims include: • Aliens exist. • 2 + 2 = 4. • Pocari Sweat is better than Aquarius. • You should kill children for fun.

Claims Claims can be: General or specific True or false Plausible or implausible Reasonable or unreasonable Supported by evidence or not…

Example: Theories Scientific theories are claims that are supported by lots of evidence, that integrate lots of our knowledge, and that explain and predict lots of phenomena.

Example: Guesses Guesses are claims that the guesser only believes might be true, or are probably true.

Example: Lies A lie is a claim that is known to be false and is made to deceive you into believing something false.

Claims Scientific theories, guesses, and lies are all claims. There are lots of other types of claims: hypotheses, deductions, considerations… A claim is something that is presented as true. Sometimes good reasons are given for accepting it, sometimes no reasons are given, and sometimes misleading reasons are given.

Critical Thinking Is there any evidence to support the claim? Is the evidence reliable and trustworthy? How reliable is it? Should you accept it? Does the evidence actually support the claim? Is there other evidence you should consider?

Critical Thinking Critical thinking involves asking these questions at the right times, knowing how to answer them, and knowing how to use those answers to accept or reject a claim. This is a skills-oriented class. These are the skills we will learn.

You Already Do It You are already a critical thinker. You use critical thinking skills all the time, even if you don’t know it.

Is there any evidence? On a lot of airlines, you are required to turn off your cell phones and other electronic devices during takeoff and landing. Claim: Keeping your devices on poses a danger. But is there any evidence that this is true? Are there studies? What do scientists say?

Is there any evidence? Flu season comes and it’s really bad. You should probably get a flu shot. Or should you go to the traditional Chinese medicine shop? They say their medicine can prevent the flu too.

How reliable is the evidence? Here’s a common story you’ll hear: Claim: Oh, you have a cold? You should get the doctor to prescribe antibiotics for you. Evidence: I got a cold and after a couple days was feeling really bad. I got some antibiotics and two days later, I felt great!

How reliable is the evidence? But this can’t be true. Colds are caused by viruses, and antibiotics only work on bacteria. The story you heard is a case of regression to the mean. People go to the doctor when they’re feeling worst. Of course they feel better later, they would feel better later anyway. Colds usually take care of themselves in 6 days.

Does the evidence support the claim? Companies often pay celebrities and other public figures to endorse their products. Claim: You should buy/ use this product. Evidence: Celebrity X buys/ uses this product. But is it any reason to buy something that some other person is paid to say they like it?

Does the evidence support the claim? But what do those doctors know about the health effects of cigarettes? Have they done studies? Maybe they smoke Camels because they’re cheaper, or because they’re “cooler” or for some other reason.

Is there other evidence to consider? Claim: Prayer heals the sick. Evidence: My mother had cancer, but then I prayed for her. Her cancer went into remission. But how many people were prayed for and not cured? How many people were not prayed for, but still had their cancer go into remission? Does prayer work or was this just an accident?

Critical Thinking Becoming a better critical thinker involves exercising these skills, asking these questions and finding out the answers, more often and more effectively and in a wider range of circumstances.

Logic This course is called Logic and Critical Thinking, and we will be learning about logic. Logic is a helpful tool for verifying the quality of arguments.

Philosophical Arguments In ordinary English, an argument is where two or more people have different views, and they heatedly or angrily discuss them. In philosophy, it’s when we present certain claims as evidence for other claims. So critical thinking is about evaluating arguments– are the claims presented as evidence true? Do they support the conclusions?

Validity An important concept in logic is validity, a particularly strong sort of evidential support. An argument is valid = if the claims presented as evidence in the argument (the “premises”) are true, then the claim that evidence supports (the “conclusion”) of the argument must be true (cannot be false).

Formally Valid Arguments Ancient philosophers (both Western and Chinese) discovered that you can tell that some arguments are valid by looking at their form alone.

Example Here’s an example of a valid argument form: Evidence: If A is true, then B is true. Evidence: A is true. Claim: Therefore, B is true. Notice that even if you don’t know what the claims A and B are, you know that if the evidence is true, then the claim is true.

Logic Logic is the study of formal validity. We try to find all the valid logical forms. That way, if we ever find an argument that has one of those forms, we will know for sure that it is valid. It wasn’t until recently that we (or a German mathematician named Gottlob Frege) found a way to find all the valid logical forms. This is the logic we learn about today.

The Limits of Logic Logic isn’t the entire story. It doesn’t have anything to say about the good arguments that are not formally valid, and it can’t identify bad arguments. There’s also another kind of “goodness” for arguments: a sound argument is valid and its premises are true. But logic alone can’t tell us what’s true.

Deciding What to Do But critical thinking does not end there. Notice that we still do not know what to do. Should I turn off my cell phone on an airplane? Should I smoke Camels? Should I eat shark fin soup if I want to avoid cancer? What do I do?

Choices A choice is a decision between two or more actions. Sometimes choices lead to the outcomes we desire with certainty. Sometimes they only likely lead to the outcome we desire. Sometimes our choices are very unlikely to get us the outcome we desire.

Choices Choices can be: Important or unimportant Easy or difficult Rational or irrational Successful or unsuccessful…

Critical Thinking What outcomes can my choice lead to? Does the outcome of my decision depend on factors other than what I choose to do? What is the likelihood that deciding to take a specific action will lead to a specific outcome? Which outcomes do I most prefer?

What outcomes can my choice lead to? Here’s an example from the United States: A lot of religious conservatives in the U.S. campaign to make abortion illegal, and elect government officials who say they will try to make it illegal. (Important background: the U.S. Supreme Court ruled that laws against abortion are unconstitutional.)

What outcomes can my choice lead to? http://www.youtube.com/watch?v=xJh6frpykQk But if abortion is illegal, presumably women who get abortions will go to jail. So do the campaigners who want to make abortion illegal want these women in jail? In the video, we see a woman who’s quite confused as to what outcome her position leads to.

What do the outcomes depend on? Sometimes, when we make a choice, the outcome depends not just on what we’ve chosen to do, but also on what others have chosen. Suppose I have a scholarship that I can offer to exactly one student to come to my school. If they don’t accept it, I cannot offer it to anyone else…

What do the outcomes depend on? If I offer it to the best student, she is most likely to decline it (she has other scholarships to other schools, she may decide to go somewhere else). If I offer it to the worst student, she is most likely to accept it (she probably has no other scholarships and no other admittances). But I don’t want to give money to the worst student!

How likely is this choice to effect this outcome? Sometimes the same action can result in different outcomes with different likelihoods. If I decide to have unprotected sex, there is some probability that I will get AIDS, some probability I will get syphilis, some probability I will not contract any STI, etc. These facts clearly matter to my decision.

Which outcomes do I most prefer? Taking different actions (making different decisions) can often lead to different outcomes. But it’s not always obvious which outcomes to prefer. Obviously $50 is better than $10. But suppose it costs the same to keep someone in jail as to pay for a student to go to college. Do you let criminals out and educate more people?

Framing and the Flu Suppose a new type of flu is spreading through China and experts predict it will move to Hong Kong soon. If nothing is done, it will kill 600. The government is deciding which of two plans to implement. They come to the following rigorous, scientifically certain evaluations of the plans:

Version 1 • If Plan A is adopted, 200 people will be saved. • If Plan B is adopted, there is a 1-in-3 chance that all 600 will be saved, and a 2-in-3 chance that no one will be saved.

Version 2 • If Plan A is adopted, 400 people will die. • If Plan B is adopted, there is a 1-in-3 chance that no one will die, and a 2-in-3 chance that all 600 will die.

Which outcomes do I prefer? Version 1 and Version 2 describe exactly the same plans. Plan A in Version 1 = Plan A in Version 2. Plan B in Version 1 = Plan B in Version 2. Yet 70% of people go with Plan A in Version 1, while only 41% choose Plan A in Version 2.

For Next Class Go to the course website: http://michaeljohnsonphilosophy.com/logic-and-critical-thinking-2013/schedule-and-readings/ Read the reading for next time.

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Critical thinking

Student Services . Critical thinking. Orientation 2011 Angela Dierks. www.bbk.ac.uk/mybirkbeck . Student Services . Critical thinking in everyday life. You think critically all the time for example when deciding not to buy a particular product

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Critical Thinking. GEA 101 Fall 2012. introduction. Course Particulars. Instructor: Dr. Michael Johnson Office: Room HSH219, Ho Sin Hang Building Office Hours: Wednesdays 15:00 to 16:00 Email: [email protected] Office Telephone: 2616 7455. Course Website.

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Critical Thinking and our Inclination Toward Faulty Logic

Critical Thinking and our Inclination Toward Faulty Logic. Arendt. Critical Thinking & our inclination toward Faulty Logic. You have the right to question what you see, hear, and read.

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LOGIC AND CRITICAL THINKING. Lecture 11 – Scientific Reasoning I. REVIEW. First, let’s go over homework from last time. REVIEW. Last time we talked about the relationship between correlation and causation.

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Critical Thinking: An Introduction. Logic and Logical Fallacies

Critical Thinking: An Introduction. Logic and Logical Fallacies. Lecture II. Truth Tables and Logical Operators. Face it…some things are either true or false (specifying this formally is called “propositional calculus”) A “proposition” is a meaningful statement

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Critical Thinking. “The important thing is not to stop questioning. Curiosity has its own reason for existing” - Albert Einstein. Critical Thinking in Your Life. Personal Life What constitutes a healthy diet? Which investment is better for my family? Why? Professional Life

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LOGIC AND CRITICAL THINKING by Karey Perkins

LOGIC AND CRITICAL THINKING by Karey Perkins. RHETORICAL APPEALS: USING LOGOS, ETHOS, PATHOS. LOGOS = LOGIC and REASON= Soundness of facts, evidence, statistics, and reasoning; soundness of authority’s statements outside self; well-documented evidence

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PHIL 002, Section 5 Logic and Critical Thinking

PHIL 002, Section 5 Logic and Critical Thinking. About this course. About this course. There’s so many of us!!!. About this course. There’s so many of us!!! Instructional staff. About this course. There’s so many of us!!! Instructional staff

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PHIL 102-01 Logic and Critical Thinking Fall 2006

PHIL 102-01 Logic and Critical Thinking Fall 2006. About this course. About this course. There’s so many of us!!!. About this course. There’s so many of us!!! Instructional staff. About this course. There’s so many of us!!! Instructional staff

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Dr. Andreas Yumarma. LOGIC AND CRITICAL THINKING. First Meeting. Sense of Logic. Study of the methods and principles used to distinguish correct from incorrect reasoning (Irving M. Copy & Carl Cohen, 1990)

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Critical thinking about critical thinking

Critical thinking about critical thinking. Paula Owens and John Hopkin. Workshop description Based on two practical activities, this workshop will explore what critical thinking means in the context of geography, apply it to some examples and consider how to apply it in the classroom

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Introductory Logic: Critical Thinking

Introductory Logic: Critical Thinking. DEFINITION. Definitions. A definition is an attempt to explain the meaning of a word by using a different word or phrase that has the same meaning. The word being defined is called the definiendum (Latin for “to be defined”).

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