PHIL102: Introduction to Critical Thinking and Logic | Saylor Academy

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Time: 40 hours

College Credit Recommended

Free Certificate

This course will introduce you to critical thinking, informal logic, and a small amount of formal logic. Its purpose is to provide you with the basic tools of analytical reasoning, which will give you a distinctive edge in a wide variety of careers and courses of study. While many university courses focus on presenting content knowledge, the emphasis here is on learning how to think effectively. Although the techniques and concepts covered here are classified as philosophical, they are essential to the practice of nearly every major discipline, from the physical sciences and medicine to politics, law, and the humanities. 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.
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- Select activity Course Syllabus
  
  Course Syllabus Page
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.
- Select activity Upon successful completion of this unit, you will ...
  Upon successful completion of this unit, you will be able to:
  distinguish between the literal and implied meanings of sentences;
  describe reportive, stipulative, precising, and persuasive definitions, and apply them to real-world scenarios;
  describe the criteria for evaluating definitions and sources, and apply them to real-world scenarios;
  distinguish between factual disputes and verbal disputes;
  define necessary and sufficient conditions, and give examples of each;
  evaluate statements for various types of obscurity, such as lexical ambiguity, referential ambiguity, syntactic ambiguity, vagueness, incompleteness, and meaning; and
  evaluate statements for distortions of meaning, such as reification, category mistakes, and poor philosophical argumentation.
- 1.1: Introduction to Critical Thinking
  - Select activity Critical Thinking
    
    Critical Thinking Page
    
    Students must
    
    Mark as done
    
    Watch this video for a basic sense of what critical thinking is and why it is important.
  - Select activity Critical Thinking Skills
    
    Critical Thinking Skills Book
    
    Students must
    
    Mark as done
    
    Read these four tutorials on critical thinking. As you read, compare the abilities that a person acquires after becoming a critical thinker with your own goals as a student, as well as with your future career and life goals.
  - Select activity Discussion: The Importance of Critical Thinking
    
    Discussion: The Importance of Critical Thinking Forum
    
    Students must
    
    Make forum posts: 1
    
    Consider these questions from a variety of angles. Then, share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
    
    Is critical thinking important? Why or why not?
    
    How will the understanding and use of critical thinking benefit you in your life now and in the future?
    
    How do emotions affect one's ability to think critically?
- 1.2: Meaning Analysis
  - 1.2.1: The Elements of Meaning
    
    Select activity Meaning Analysis
    
    Meaning Analysis Book
    
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    While meaning may not seem like the sort of thing that needs explaining, the ways in which it is produced, both in speech and in writing, can lead to confusion and thus warrant close examination.
    
    In this section, you will read about the nature of linguistic meaning, the different types of definitions, the difference between literal meaning and conversational implicature, and the difference between verbal and factual disputes.
    
    Complete the exercises to enhance your critical thinking skills and your understanding of meaning.
    
    Select activity Discussion: Definitions
    
    Discussion: Definitions Forum
    
    Students must
    
    Make forum posts: 1
    
    Evaluate these definitions. If you find a definition inadequate or flawed, try to provide a better definition. Then, share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
    Discuss Mark Twain's definition of love: "Love is the irresistible desire to be irresistibly desired."
    Discuss this definition of a cloud: "A cloud is a large, semi-transparent mass with fleecy texture suspended in the atmosphere whose shape is subject to continual change."
  - 1.2.2: Necessary and Sufficient Conditions
    
    Select activity Necessity and Sufficiency
    
    Necessity and Sufficiency Page
    
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    Phenomena in the world are related to one another in all sorts of complicated ways. Sometimes we can say very generally whether one thing is necessary for something else or whether it is merely sufficient. The concepts of necessary and sufficient conditions help us understand and explain the different kinds of connections between concepts and how different states of affairs are related to each other.
  - 1.2.3: Thinking Critically about Ordinary Language
    
    Select activity Meaning Analysis Continued
    
    Meaning Analysis Continued Book
    
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    Thinking needs to be precise and clear, but the language we use to express our thoughts is often imprecise and misleading. In this section, you will read about identifying common ways language can lead us astray.
    
    Complete all exercises and check your answers.
- 1.3: Assessing Sources
  - Select activity Research Skills Tutorial
    
    Research Skills Tutorial Book
    
    Students must
    
    Mark as done
    
    Read this tutorial, which discusses appropriate questions to ask to determine whether a source is credible and reliable. As you read, make a list of important questions to ask. Make notes under each question about why that question is important. Also, write down any tips to consider when answering each question.
  - Select activity Evaluating Sources and Peer Review
    
    Evaluating Sources and Peer Review Page
    
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    Mark as done
    
    Watch these videos to learn about the basic principles of evaluating sources. The first video identifies characteristics of scholarly articles, and the second video explains the "peer review" editorial process.
  - Select activity Evaluating Internet Material
    
    Evaluating Internet Material Page
    
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    Mark as done
    
    Read this article, which explains factors relevant to assessing the reliability of Internet sources. Many of the factors mentioned in this material are also relevant to assessing the reliability of other sources.
  - Select activity Discussion: Finding and Assessing Sources
    
    Discussion: Finding and Assessing Sources Forum
    
    Students must
    
    Make forum posts: 1
    
    Consider your experiences with finding and assessing sources. In particular, using a personal experience as an example, discuss whether and to what extent one of the strategies in this section for evaluating sources has been or would have been helpful. Then, share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
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.
- Select activity Upon successful completion of this unit, you will ...
  Upon successful completion of this unit, you will be able to:
  construct valid and sound arguments using the standard form of an argument;
  determine if a counterexample exists for a given argument;
  illustrate valid argument patterns such as modus ponens, modus tollens, hypothetical syllogism, disjunctive syllogism, constructive dilemma, and reductio ad absurdum;
  identify hidden and implicit assumptions in an argument;
  explain the differences between deductive reasoning and inductive reasoning;
  explain the pattern of inductive reasoning called an analogical argument;
  construct an argument map for an argument; and
  apply the criteria for evaluating the strength of an argument to any given argument.
- 2.1: The Nature of Arguments
  - 2.1.1: What Are Arguments?
    
    Select activity What is an Argument?
    
    What is an Argument? Book
    
    Students must
    
    Mark as done
    
    Read this section, which differentiates an argument in the logical sense from the ordinary language sense of a heated disagreement and introduces you to the basic structures of logical argument: statements, premises, and conclusions.
    
    Complete Exercise 1, identifying which sentences are statements. Once you identify them, begin thinking about what premises might lead to those statements. When you finish, check your responses with the answer key.
    
    If you would like to download the full textbook, it can be found here: Introduction to Logic and Critical Thinking.
    
    Select activity More on Arguments
    
    More on Arguments Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which explains how to identify an argument by picking out its components. Complete the exercises and check your answers.
  - 2.1.2: How to Tell an Argument from a Non-Argument
    
    Select activity Identifying Arguments
    
    Identifying Arguments Book
    
    Students must
    
    Mark as done
    
    Read this section, which will give you some tips on how to spot an argument. While the premise and conclusion indicators are not guarantees of an argument, they can assist you in identifying an argument.
    
    Complete Exercise 2, distinguishing arguments from non-arguments and identifying the conclusion of argument sentences. Despite the name, the conclusion often precedes the premises when we present arguments in ordinary language. When you finish the exercise, check your answers against the answer key.
    
    Select activity The Standard Format of an Argument
    
    The Standard Format of an Argument Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which explains how to put an argument in standard form. Be sure to complete the exercise.
- 2.2: Good Argument Form
  - Select activity Validity and Soundness
    
    Validity and Soundness Book
    
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    Mark as done
    
    These sections will introduce you to the concept of validity – the term for when the conclusion of an argument follows from its premises. Pay careful attention to the difference between validity and soundness. All sound arguments are valid, but not all valid arguments are sound. Remember that premises do not have to be true for an argument to be valid.
    Complete Exercise 5, checking your answers against the key.
  - Select activity Validity, Soundness, and Valid Patterns
    
    Validity, Soundness, and Valid Patterns Book
    
    Students must
    
    Mark as done
    
    Validity and soundness are two of the most important concepts in the study of arguments, and they are often confused with one another. Read these three tutorials on the distinction between valid and sound arguments, their relationship to the truth of the statements that make them up, and the structural patterns that help us to recognize them.
    Complete the exercises and check your answers.
  - Select activity Quiz on Truth, Validity, and Soundness
    
    Quiz on Truth, Validity, and Soundness Page
    
    Students must
    
    Mark as done
    
    Complete this knowledge check, which tests your knowledge of the distinction between valid and sound arguments. Note that deductive arguments might be, but need not be, valid or sound; deductive arguments may be valid or invalid and sound or unsound.
  - Select activity Rounding Out Arguments
    
    Rounding Out Arguments Book
    
    Students must
    
    Mark as done
    
    Read these sections to learn how to round out arguments conceptually. The first section will distinguish between two types of argument: deductive and inductive. Pay careful attention to the difference between these two, and think about which kind of argument you use more often. The second section will help you identify arguments with a missing premise and determine how and when to supply this missing premise. It will also introduce you to the principle of charity and the difference between normative and descriptive statements – three very important terms! The third section shows you three rhetorical devices to hint at further argument without actually going through the argument: assuring, guarding, and discounting.
    Complete the exercises, then check your answers against the keys.
  - Select activity Hidden Assumptions, Inductive Reasoning, and Good Arguments
    
    Hidden Assumptions, Inductive Reasoning, and Good Arguments Book
    
    Students must
    
    Mark as done
    
    When arguments are stated verbally or in writing, their structure may not be completely explicit. The section on hidden assumptions provides clues about how to identify hidden assumptions. The section on inductive reasoning introduces the important concept of induction. Inductive arguments form a whole second class of arguments, alongside deductive ones, and will be important in our unit on scientific reasoning later on. The final section puts together a number of the ideas laid out so far to describe the characteristics of a good argument.
    
    Complete the exercises and check your answer.
- 2.3: Visualizing How Arguments Work
  - Select activity More Complex Argument Structures
    
    More Complex Argument Structures Book
    
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    Visualizing argument structure can help determine how directly or indirectly supporting evidence leads to a conclusion. This section gives examples of simple and more complex arguments using arrows to represent the structure of an argument. Complete the exercises and then check your answers. The answer key has the arguments in standard form, but there is no key for the diagramming.
  - Select activity Argument Mapping
    
    Argument Mapping Page
    
    Students must
    
    Mark as done
    
    Read this tutorial about how to construct an argument map. Argument maps are a way of visually representing the logical structure of an argument.
- 2.4: Analogical Arguments
  - Select activity Analogical Arguments
    
    Analogical Arguments Book
    
    Students must
    
    Mark as done
    
    Read this section about an inductive argument many people use quite frequently: arguments from analogy. As you read, think about the difference between relevant and irrelevant similarities when it comes to analogies, as well as relevant disanalogies. Being able to identify these will help you make stronger inductive arguments.
    Complete the exercise and check your work against the answer key.
  - Select activity More on Analogical Arguments
    
    More on Analogical Arguments Page
    
    Students must
    
    Mark as done
    
    Read this tutorial on analogical arguments. Arguments that are based on analogies have certain inherent weaknesses. This tutorial will help you find out how analogical arguments are structured and the most common ways they may be undermined.
- 2.5: Valid Argument Patterns
  - Select activity Valid Argument Patterns
    
    Valid Argument Patterns Page
    
    Students must
    
    Mark as done
    
    Read this tutorial on reducing valid arguments to their basic structure using argument patterns. This text previews the kind of analysis we will do much more of in Unit 4. This kind of strategy is sometimes useful in analyzing arguments in real-life situations. For example, you might see these types of questions and find identifying argument patterns useful for the Law School Admission Test (LSAT).
- 2.6: Review of Argument Analysis
  - Select activity Discussion: Argument Analysis
    
    Discussion: Argument Analysis Forum
    
    Students must
    
    Make forum posts: 1
    
    Try to formulate examples of three important patterns of argument: modus ponens, modus tollens, and reductio. Then, for this argument sent to a newspaper by a reader responding to an article claiming that Shakespeare was Italian, identify the argument's main conclusion and spell out the argument's premises.
    "So Shakespeare was an Italian, because almost half of his plays are set in Italy. Almost all of Isaac Asimov's novels are set in outer space – does that mean he was a Martian?" – Graham Simpson
    Share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.

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.

Select activity Upon successful completion of this unit, you will ...
Upon successful completion of this unit, you will be able to:

contrast formal logic and informal logic;

identify declarative, interrogative, and imperative sentences;

define and identify several kinds of logical statements: negations, conjunctions, disjunctions, conditionals, and biconditionals;

identify the scope and main connective for a well-formed formula;

create truth-tables for several kinds of statements, sentences and arguments, such as negations, conjunctions, disjunctions, conditionals, and biconditionals;

translate ordinary statements into logical language; and

explain the limitations of truth-tables as assessment tools.

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.
- Select activity Upon successful completion of this unit, you will ...
  Upon successful completion of this unit, you will be able to:
  
  create Venn diagrams as a means to represent and reason about relationships among classes;
  
  evaluate the validity of arguments using Venn diagrams; and
  
  describe the limitations of Venn diagrams as assessment tools.
- 4.1: Introduction to Venn Diagrams
  - 4.1.1: Venn Diagrams as Illustrations of Sets or Classes
    
    Select activity Categorical Logic and The Venn Test of Validity for Immediate Categorical Inferences
    
    Categorical Logic and The Venn Test of Validity for Immediate Categorical Inferences Book
    
    Students must
    
    Mark as done
    
    Read these sections to learn and apply a visual method for determining the validity of categorical inferences: Venn diagrams. Note the four categorical forms and what they mean: universal affirmative, universal negative, particular affirmative, and particular negative. Get comfortable drawing Venn diagrams for categorical statements and shading in the area or drawing a star for the statements you are given.
    Complete the exercises, checking your answers against the answer keys, translating the diagrams into statements, and using the Venn test of validity to determine the validity of the given categorical inferences.
    
    Select activity Basic Notation
    
    Basic Notation Page
    
    Students must
    
    Mark as done
    
    Read the introduction and tutorial for an introduction to Venn diagrams. In Venn diagrams, circles represent sets or classes. These tutorials demonstrate how to use shading and overlapping to illustrate empty sets and relations of all, every, and nothing.
  - 4.1.2: More Complicated Venn Diagrams
    
    Select activity Venn Diagram Exercises
    
    Venn Diagram Exercises Page
    
    Students must
    
    Mark as done
    
    Working with Venn diagrams involving three circles is almost the same as working with two circles. The only difference is that there are now eight distinct regions, each with a specific logical meaning.
    Complete these exercises and check your answers.
  - 4.1.3: Illustrating Experience with Venn Diagrams
    
    Select activity Universal Statements and Existential Commitment
    
    Universal Statements and Existential Commitment Book
    
    Students must
    
    Mark as done
    
    Read this section to learn about a potentially counter-intuitive relationship between universal and particular affirmatives – namely, one does not imply the other. This is because universal affirmatives do not contain an "existential commitment": a statement that there is anything in the category the universal affirmative references.
    Complete the exercise, keeping in mind that universal affirmatives do not contain existential commitments. Check your validity answers against the key.
  - 4.1.4: Review of Introduction to Venn Diagrams
    
    Select activity More Venn Diagram Exercises
    
    More Venn Diagram Exercises Page
    
    Students must
    
    Mark as done
    
    Complete these exercises relating to two-circle Venn diagrams. For each question, you must choose the sentence that best represents what is shown in the given diagram.
- 4.2: Venn Diagrams and Arguments
  - 4.2.1: Using Venn Diagrams to Evaluate Syllogisms
    
    Select activity Venn Validity for Categorical Syllogisms
    
    Venn Validity for Categorical Syllogisms Book
    
    Students must
    
    Mark as done
    
    Read this section on Venn diagrams, which will help you use Venn diagrams to test the validity of whole categorical syllogisms rather than only categorical inferences. Read the section and identify the categories in every statement of the syllogisms as you go, making your own Venn diagrams to test the validity, as directed.
    Complete the exercise, checking your validity answers against the key.
    
    Select activity Syllogism
    
    Syllogism Page
    
    Students must
    
    Mark as done
    
    Read this tutorial on how to use Venn diagrams to evaluate arguments. You will be introduced to the concept of a syllogism, a special type of argument that cannot be evaluated in SL. Venn diagrams are ideal for evaluating this type of argument. Remember that a Venn diagram can only tell us if an argument is valid, not whether it is sound.
  - 4.2.2: Understanding the Logic of Venn Diagrams
    
    Select activity The Logic of Venn Diagrams
    
    The Logic of Venn Diagrams Page
    
    Students must
    
    Mark as done
    
    This page reviews how to set up Venn diagrams and the rules for using Venn diagrams in evaluating argument validity. It also introduces the notion of conditional validity and explains how to use Venn diagrams to evaluate the validity of categorical syllogisms.
  - 4.2.3: The Limitations of Venn Diagrams
    
    Select activity Limitations of Venn Diagrams
    
    Limitations of Venn Diagrams Page
    
    Students must
    
    Mark as done
    
    Read this tutorial about the limitations of Venn diagrams. Although Venn diagrams are a powerful tool for representing some types of statements, there are many statements that they cannot handle.
    
    Complete the exercises for this tutorial, then check your answers.
  - 4.2.4: Review of Venn Diagrams and Arguments
    
    Select activity Even More Venn Diagram Exercises
    
    Even More Venn Diagram Exercises Page
    
    Students must
    
    Mark as done
    
    Complete these exercises to determine whether these arguments are valid or not. Draw out the Venn diagrams with pencil and paper.
    
    Select activity Discussion: Venn Diagrams and Argument Validity
    
    Discussion: Venn Diagrams and Argument Validity Forum
    
    Students must
    
    Make forum posts: 1
    
    Consider how you might adapt Venn diagrams to evaluate the validity of these arguments.
    Most cooks are men. Most men are idiots. So most cooks are idiots.
    Very few plants are purple. Very few purple things are edible. So very few plants are edible.
    Share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
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.
- Select activity Upon successful completion of this unit, you will ...
  Upon successful completion of this unit, you will be able to:
  explain fallacies of inconsistency, irrelevance, insufficiency, and inappropriate presumption;
  identify common fallacies, including the straw man, gambler's fallacy, begging the question, red herring, ad hominem, appeal to ignorance, appeal to people, complex question, loaded question, and non-sequitur; and
  describe the nature of a cognitive bias and identify examples of cognitive bias.
- 5.1: Introduction to Fallacies
  - Select activity What is a Fallacy?
    
    What is a Fallacy? Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which introduces the notion of fallacious reasoning. Fallacies are arguments that are frequently accepted as valid but contain subtle reasoning errors. It is important to know how to catch fallacies.
- 5.2: Types of Fallacies
  - Select activity Formal versus Informal Fallacies
    
    Formal versus Informal Fallacies Page
    
    Students must
    
    Mark as done
    
    Read this section to learn the difference between formal and informal fallacies and learn two key formal fallacies that look like good logic but are not: denying the antecedent and affirming the consequent. There is a popular joke among philosophers about Descartes (the French philosopher who famously wrote, "I think, therefore I am") walking into a bar and, when the bartender asks if he'd like a drink, replying "I think not" and vanishing in a puff. While delightful to share among your philosopher friends, this joke actually falls prey to one of these fallacies – see if you can tell why.
  - Select activity List of Fallacies
    
    List of Fallacies Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which defines the most common fallacies. This list narrows down some of the fallacies in the previous text and is enough to get us started. We will look at a wider sample of fallacies later in this course. For now, focus on defining each fallacy and identifying the differences between the fallacies on the list.
  - Select activity False Dichotomy, Causal Slippery Slope, and Appeal to Authority
    
    False Dichotomy, Causal Slippery Slope, and Appeal to Authority Page
    
    Students must
    
    Mark as done
    
    Read these sections to review three important fallacies you probably come across without realizing it: false dichotomy, causal slippery slope fallacy, and appeal to authority.
    
    All three of these fallacies can be disguised as something that looks logical, but these readings will help you identify when that is not the case.
  - Select activity Inconsistency, Irrelevance, Insufficiency, and Inappropriate Presumption
    
    Inconsistency, Irrelevance, Insufficiency, and Inappropriate Presumption Book
    
    Students must
    
    Mark as done
    
    Read these tutorials, which introduce four major classifications of fallacies. Although there are many possible ways of categorizing fallacies, the four major groups discussed in these tutorials are fairly standard.
  - Select activity Exercises on Fallacies
    
    Exercises on Fallacies Page
    
    Students must
    
    Mark as done
    
    Complete this quiz, which will help you identify common fallacies.
- 5.3: Ten Common Fallacies in Detail
  - 5.3.1: Straw Man Fallacy
    
    Select activity Straw Man Argument
    
    Straw Man Argument Page
    
    Students must
    
    Mark as done
    
    You may have heard criticisms of a "straw man" argument before and not known what that meant. This section walks you through a straw man argument and gives examples. After reading this section, try to come up with a few examples of straw man arguments, and look for straw man fallacies in your own life.
    
    Select activity The Straw Man Fallacy
    
    The Straw Man Fallacy Page
    
    Students must
    
    Mark as done
    
    Watch this video, which explains a fallacy commonly known as the straw man fallacy. After watching this video, you should be able to define the fallacy and identify examples of the fallacy.
  - 5.3.2: Gambler's Fallacy
    
    Select activity The Gambler's Fallacy
    
    The Gambler's Fallacy Page
    
    Students must
    
    Mark as done
    
    Watch this video, which explains a fallacy commonly known as the gambler's fallacy. After watching this video, you should be able to define the fallacy and identify examples of the fallacy.
    
    Select activity More on the Gambler's Fallacy
    
    More on the Gambler's Fallacy Page
    
    Students must
    
    Mark as done
    
    Read this introduction to the gambler's fallacy and the example of how it works.
  - 5.3.3: Begging the Question
    
    Select activity Begging the Question
    
    Begging the Question Page
    
    Students must
    
    Mark as done
    
    Read this section on the fallacy of "begging the question". When we formalize the examples in the premise, they are not substantively different from the conclusion. Look out for "question begging" arguments in your life.
  - 5.3.4: Red Herring
    
    Select activity The Red Herring Fallacy
    
    The Red Herring Fallacy Page
    
    Students must
    
    Mark as done
    
    Read this article to learn about the red herring fallacy. If you think bringing up colorful fish sounds out of place when discussing logic, then you're right! The red herring fallacy operates by bringing up irrelevant information. Often when we have arguments in our lives, though, people throw in "red herrings".
  - 5.3.5: Ad Hominem (Against the Person)
    
    Select activity Ad Hominem
    
    Ad Hominem Page
    
    Students must
    
    Mark as done
    
    You have doubtless heard ad hominem attacks before – though you may not have known they were an informal fallacy. Read this section on the ad hominem fallacy for a definition and examples of these attacks. After reading, you should be able to identify ad hominem attacks when you encounter them.
  - 5.3.6: Ad Ignorantium (Appeal to Ignorance)
    
    Select activity Appeal to Ignorance
    
    Appeal to Ignorance Page
    
    Students must
    
    Mark as done
    
    Read this brief description of the "ad ignorantium" (or "appeal to ignorance") fallacy. This common fallacy insists on placing the burden of proof on whatever side opposes it.
  - 5.3.7: Ad Populum (Appeal to the People)
    
    Select activity Appeal to the People
    
    Appeal to the People Page
    
    Students must
    
    Mark as done
    
    Read this article for a quick explanation and examples of the logical fallacy ad populum, or "appeal to the people". This fallacy relies on our social inclinations and is popularly seen in advertising. Despite the effectiveness of these kinds of appeals, they nonetheless are not logical arguments.
  - 5.3.8: Complex Question (Double-Barreled Question)
    
    Select activity Double-Barreled Question
    
    Double-Barreled Question Page
    
    Students must
    
    Mark as done
    
    Read this article, which defines the double-barreled question fallacy and identifies examples of it.
  - 5.3.9: Loaded Question
    
    Select activity Loaded Question
    
    Loaded Question Page
    
    Students must
    
    Mark as done
    
    Read this article, which defines the loaded question fallacy and identifies examples of it.
  - 5.3.10: Non Sequitur (It Does Not Follow)
    
    Select activity Formal Fallacy (<em>Non Sequitur</em>)
    
    Formal Fallacy (Non Sequitur) Page
    
    Students must
    
    Mark as done
    
    Read this article, which defines the non sequitur fallacy and identifies examples of it.
  - 5.3.11: Review of Fallacies
    
    Select activity Discussion: Fallacies
    
    Discussion: Fallacies Forum
    
    Students must
    
    Make forum posts: 1
    
    Consider the passages below. If the passage contains an argument, identify the premises and main conclusion. For each passage, assess whether it contains a fallacy. If it does, identify the fallacy and explain why you made your assessment.
    God exists because many people who believe in God go on to have healthy, happy, and meaningful lives.
    Bertrand Russell (1872–1970), the British philosopher, said that objective morality is possible without God. Russell was an atheist, and we all know that he slept around and seduced young girls and was nasty to many people.
    Do you want four more years of this person in political office? Vote for me, Candidate X.
    Share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
- 5.4: Cognitive Biases
  - Select activity Cognitive Biases
    
    Cognitive Biases Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which describes some examples of cognitive biases. These biases are ways of thinking that lead us to make poor inferences. Being able to identify cognitive biases helps us to improve our reasoning and helps us to assess other people's reasoning.
  - Select activity Cognitive Biases Explained
    
    Cognitive Biases Explained Page
    
    Students must
    
    Mark as done
    
    Watch this video to learn about availability, representativeness, and confirmation biases. Note that there are many other cognitive biases, including anchoring bias, availability heuristic bias, bandwagon bias, choice supportive bias, ostrich bias, outcome bias, overconfidence, placebo bias, survivorship bias, selective perception bias, and blind spot bias. Try to identify some examples of cognitive biases in your life.
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.
- Select activity Upon successful completion of this unit, you will ...
  Upon successful completion of this unit, you will be able to:
  
  explain the hypothetico-deductive method and its implications for testing scientific hypotheses;
  
  explain Occam's Razor and its implications in real-world scenarios;
  
  explain the criteria scientists use to choose among competing hypotheses;
  
  discuss notions of causation, causal relations, and Mill's methods for reasoning about causation;
  
  explain the difference between correlation and causation;
  
  use visualization tools to represent causal relations; and
  
  explain several common fallacies when reasoning about causation, such as false cause.
- 6.1: The Basic Principles of Scientific Reasoning
  - Select activity The Hypothetical-Deductive Method
    
    The Hypothetical-Deductive Method Page
    
    Students must
    
    Mark as done
    
    Read these tutorials on scientific reasoning. Science is almost infinitely varied, but its basic method is surprisingly simple. These tutorials will introduce the four components of the hypothetical-deductive method and the difference between truth and confirmation.
  - Select activity The Scientific Method Explained by a Scientist
    
    The Scientific Method Explained by a Scientist Page
    
    Students must
    
    Mark as done
    
    Watch these videos. Pay attention to the discussion of the difference between the terms theory and evidence and the discussion of the reasoning method called Ockham's Razor (also sometimes called Occam's Razor).
  - Select activity What Makes One Scientific Theory Better than Another?
    
    What Makes One Scientific Theory Better than Another? Page
    
    Students must
    
    Mark as done
    
    Read this tutorial on theory choice. In scientific practice, multiple theories will frequently be put forward to explain the same phenomena. When this happens, scientists sometimes use five criteria to guide their decisions among alternative theories.
  - Select activity Discussion: Scientific Theories
    
    Discussion: Scientific Theories Forum
    
    Students must
    
    Make forum posts: 1
    
    Consider these prompts. Share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
    
    Given what you know about criteria for theory choice in science, such as predictive power, mechanism, fruitfulness, simplicity, and coherence, is there anything other than evidence scientists use to determine whether to accept a theory? Should there be?
    
    Are simpler theories more likely to be true? Is Ockham's Razor always a good rule of scientific reasoning?
- 6.2: The Question of Causality
  - 6.2.1: The Basics of Causality
    
    Select activity Causal Reasoning
    
    Causal Reasoning Book
    
    Students must
    
    Mark as done
    
    Read this section to investigate the complications of causality, particularly as it relates to correlation. Sometimes, two correlated events share a common cause, and sometimes, correlation is accidental. Complete the exercises to practice determining sufficient evidence for causation and determining accidental correlation. Check your answers against the key.
    
    Select activity Causation
    
    Causation Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which outlines some important terminological distinctions for causation. Causation is an ideal topic to address in a course on critical thinking because it is something we feel we understand well in our everyday lives. Once we begin trying to think scientifically about causes, however, we find that fixing the causes of some events requires precision and subtlety.
    
    Select activity Mill's Methods
    
    Mill's Methods Page
    
    Students must
    
    Mark as done
    
    Read this tutorial about Mill’s five methods for identifying causes. John Stuart Mill (1806-1873), the 19th-century English philosopher, proposed five distinct ways to identify a cause through observation. While these methods may appear to be common sense, it is important to see that they represent distinct modes of inference.
  - 6.2.2: Causality is More Than Just Cause and Effect
    
    Select activity Causal Inferences
    
    Causal Inferences Page
    
    Students must
    
    Mark as done
    
    Read this tutorial on causality, which identifies seven different types of causal relations. Each type of relation is followed by a set of defining criteria. Although each type of relation is a cause-and-effect relationship between A and B, information about the context of the interaction and the relation of A and B to one another in time affects what we can say about the causal relation between them.
    
    Select activity Correlation and Causation
    
    Correlation and Causation Page
    
    Students must
    
    Mark as done
    
    Read this example-rich tutorial, which explains the difference between the two relationships of correlation and causation. Scientists looking for cause-and-effect relationships in the natural world need to be careful not to misconstrue causality with mere correlation.
    
    Select activity Causal Diagrams
    
    Causal Diagrams Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which illustrates two ways of diagramming cause and effect. They allow for the description of multiple causes and effects from a single event and for distinguishing between levels of causation.
    
    When multiple relations of cause and effect are involved in the behavior of some phenomenon, representing these relations visually is often the best way to get a handle on them and to assist in quantitative analysis of the system in question.
    
    Select activity Discussion: Causation
    
    Discussion: Causation Forum
    
    Students must
    
    Make forum posts: 1
    
    This passage is an excerpt from a report by the Arizona Daily Wildcat (June 16, 1999) concerning a study to show that certain people can communicate with the dead. Using what you have learned about causation, correlation, and causal fallacies, consider the potential flaws with the experiment. Assume that the report is mostly correct. Summarize your evaluation of the flaws in the experiment. Share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
    "Gary Schwartz, psychology professor and co-founder of the University of Arizona Human Energy Systems Lab, speaks about his work at the University of Arizona. A team of scientists and students conducted a unique experiment this weekend, probing the possibility of an afterlife by studying how mediums commune with the dead.
    Researchers invited a panel of mediums to meet with 10 people whose loved ones had recently died. While under observation, the mediums tried to receive information from the deceased without prior knowledge about the deceased. Schwartz invited four mediums to participate in the study, including famous "superstars" of the psychic world, such as author John Edwards, and unknowns, such as California housewife Laurie Campbell. The medium sat facing a wall while a researcher looked on. A "sitter," who had recently lost a relative or friend, would then enter the room and sit six feet behind the medium. Schwartz acknowledged that a few of the sitters were acquaintances of the mediums.
    For up to 10 minutes, the medium and the sitter would sit in silence. The medium, who could not see the sitter, would concentrate on receiving psychic impressions. A question and answer session followed, in which the sitter was allowed only to answer "yes" or "no." Schwartz said the study was set up to minimize communication between the medium and the sitter, avoiding conscious or subconscious prompting between the two. While the final results have not been written up, Schwartz said he was impressed with the mediums' performance. He said that on several occasions the mediums were able to pick out the names and personal information of the deceased."
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.
- Select activity Upon successful completion of this unit, you will ...
  Upon successful completion of this unit, you will be able to:
  illustrate several types of problems and explain how to understand and problem-solve each;
  use visualization tools to analyze problems;
  explain the principles of creative thinking and their implications; and
  compare the methods for approaching problems creatively as a means to think creatively about real-world problems.
- 7.1: Strategic Reasoning
  - Select activity Classifying Problems
    
    Classifying Problems Page
    
    Students must
    
    Mark as done
    
    Read this tutorial about what to consider when defining a problem and the three major classifications that problems usually fall under. Problem-solving is an activity that combines skills of critical and creative thinking. The first task in any problem-solving scenario is to identify the type of problem one is dealing with.
    
    Complete the exercises for this tutorial, and check your answers.
  - Select activity Solving Problems
    
    Solving Problems Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which outlines the mathematician George Pólya’s four-step problem-solving procedure.
  - Select activity Complex Systems
    
    Complex Systems Page
    
    Students must
    
    Mark as done
    
    Read this tutorial, which introduces the technique of process analysis. This course has focused primarily on problems that are relatively simple in structure. You should be aware that many problems encountered will be highly complex, involving multiple variables and a mixture of problem types. You will read about flowcharts next.
  - Select activity Charts and Diagrams
    
    Charts and Diagrams Page
    
    Students must
    
    Mark as done
    
    Read this section on flowcharts. It may also be helpful to review subunit 6.2.5 on cause-and-effect diagrams. There are several useful visual techniques to facilitate solving complex problems.
  - Select activity Making Good Decisions
    
    Making Good Decisions Page
    
    Students must
    
    Mark as done
    
    Read this tutorial about basic decision-making rules. Decision theory provides tools for evaluating the best course of action in scenarios involving risk and uncertainty.
- 7.2: Creative Thinking
  - Select activity Three Basic Principles of Creative Thinking
    
    Three Basic Principles of Creative Thinking Page
    
    Students must
    
    Mark as done
    
    Read this tutorial on principles of creative thinking. Creativity is a ubiquitous human activity, not just the province of artists and inventors. Human beings solve problems creatively every day. The nature of creativity thus incorporates both spectacular creative acts and more modest instances of creative reasoning. This tutorial explains what all forms of creativity have in common.
  - Select activity The Creativity Cycle
    
    The Creativity Cycle Page
    
    Students must
    
    Mark as done
    
    Read this tutorial on the creativity cycle. Although something remains mysterious about what occurs during a flash of creative inspiration, there are nonetheless certain procedures that encourage creative thinking. This tutorial outlines a repeatable four-step creative process based on what is known objectively about producing novel ideas and solutions.
  - Select activity Creative Heuristics and Group Creativity
    
    Creative Heuristics and Group Creativity Page
    
    Students must
    
    Mark as done
    
    Read these tutorials, which offer procedures for initiating creative thinking based on our existing factual knowledge. The quotations in the second tutorial demonstrate how these procedures form part of the creative process of some of the most famous minds in art, science, and philosophy.
  - Select activity Discussion: Creative Thinking
    
    Discussion: Creative Thinking Forum
    
    Students must
    
    Make forum posts: 1
    
    Consider your experiences with thinking creatively. In particular, using a personal experience as an example, discuss whether and to what extent one of the strategies in this section for thinking creatively has been or would have been helpful.
    Share your thoughts on the discussion forum. Make sure to review and respond to other students' posts, as well.
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!
- Select activity PHIL102 Study Guide
  
  PHIL102 Study Guide Book
Course Feedback Survey
Please take a few minutes to give us feedback about this course. We appreciate your feedback, whether you completed the whole course or even just a few resources. Your feedback will help us make our courses better, and we use your feedback each time we make updates to our courses. If you come across any urgent problems, email contact@saylor.org.
- Select activity Course Feedback Survey
  
  Course Feedback Survey URL
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.
- Select activity PHIL102: Certificate Final Exam
  
  PHIL102: Certificate Final Exam Quiz
  
  Students must
  
  Receive a grade
  
  Receive a passing grade
Saylor Direct Credit
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.

We are partnering with SmarterProctoring to help make the proctoring fee more affordable. We will be recording you, your screen, and the audio in your room during the exam. This is an automated proctoring service, but no decisions are automated; recordings are only viewed by our staff with the purpose of making sure it is you taking the exam and verifying any questions about exam integrity. We understand that there are challenges with learning at home - we won't invalidate your exam just because your child ran into the room!

Requirements:

Desktop Computer

Chrome (v74+)

Webcam + Microphone

1mbps+ Internet Connection

Once you pass this final exam, you will be awarded a Credly Badge and can request an official transcript.

Saylor Direct Credit Exam

This exam is part of the Saylor Direct College Credit program. Before attempting this exam, review the Saylor Direct Credit page for complete requirements.

Essential exam information:

You must take this exam with our automated proctor. If you cannot, please contact us to request an override.

The automated proctoring session will cost $5.

This is a closed-book, closed-notes exam (see allowed resources below).

You will have two (2) hours to complete this exam.

You have up to 3 attempts, but you must wait 14 days between consecutive attempts of this exam.

The passing grade is 70% or higher.

This exam consists of 50 multiple-choice questions.

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Exam questions are distributed across multiple pages.

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Gather these resources before you start your exam.

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Gather these before you start your exam:

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You will require at least 1mbps of internet bandwidth. Ask others sharing your connection not to stream during your exam.

Take a deep breath; you got this!

Name	Meaning	Symbol 1	Symbol 2
Conjunction	and	&	•
Disjunction	or	v	v
Negation	not	~	~
Conditional	if/then	→	⊃
Biconditional	if and only if	↔	≡

COURSE INTRODUCTION

Course Syllabus

Unit 1: Introduction and Meaning Analysis

1.1: Introduction to Critical Thinking

Critical Thinking

Critical Thinking Skills

Discussion: The Importance of Critical Thinking

1.2.1: The Elements of Meaning

Meaning Analysis

Discussion: Definitions

1.2.2: Necessary and Sufficient Conditions

Necessity and Sufficiency

1.2.3: Thinking Critically about Ordinary Language

Meaning Analysis Continued

1.3: Assessing Sources

Research Skills Tutorial

Evaluating Sources and Peer Review

Evaluating Internet Material

Discussion: Finding and Assessing Sources

Unit 2: Argument Analysis

2.1.1: What Are Arguments?

What is an Argument?

More on Arguments

2.1.2: How to Tell an Argument from a Non-Argument

Identifying Arguments

The Standard Format of an Argument

2.2: Good Argument Form

Validity and Soundness

Validity, Soundness, and Valid Patterns

Quiz on Truth, Validity, and Soundness

Rounding Out Arguments

Hidden Assumptions, Inductive Reasoning, and Good Arguments

2.3: Visualizing How Arguments Work

More Complex Argument Structures

Argument Mapping

2.4: Analogical Arguments

Analogical Arguments

More on Analogical Arguments

2.5: Valid Argument Patterns

Valid Argument Patterns

2.6: Review of Argument Analysis

Discussion: Argument Analysis

Unit 3: Basic Sentential Logic

3.1: The Basics of Logic

What is Logic?

3.1.1: Logical Statements, Connectives, and Relations

Formal Methods of Evaluation

Statements, Logical Connectives, and Logical Relations

3.1.2: Logic Puzzles

Fun Logic Puzzles

The World's Hardest Logic Puzzle Ever!

3.2.1: How to Write Sentences in Sentential Logic

Propositional Logic Functions

Sentential Logic and Well-Formed Formulas

3.2.2: Connectives and Truth Tables

Truth Tables

Connectives

3.2.3: How to Draw Truth Tables for More Complicated Statements

Complex Truth Tables

3.2.4: Properties of Individual Well-Formed Formulas and Relations Between Them

Relationships in Truth Statements

Properties and Relations

3.2.5: Understanding Truth Tables

Understanding Truth Tables

3.2.6: How to Translate Ordinary Statements into Symbolic Formulae

Formalization

3.2.7: Formalization Practice

Propositional Logic and Symbolization

3.2.8: Two Methods for Determining the Validity of an Argument

Validity and the Indirect Method

3.2.9: Why Sentential Logic Is Not Enough

Material Conditional

Unit 4: Venn Diagrams

4.1.1: Venn Diagrams as Illustrations of Sets or Classes

Categorical Logic and The Venn Test of Validity for Immediate Categorical Inferences

Basic Notation

4.1.2: More Complicated Venn Diagrams

Venn Diagram Exercises

4.1.3: Illustrating Experience with Venn Diagrams

Universal Statements and Existential Commitment