WGU D265 Critical Thinking Class

Critical Thinking and Reasoning Terms

Critical Thinking and Reasoning Class: Technical Terms

Section 1: Technical Terms/Concepts

Basic Components

  1. Proposition

    • Definition: A statement that expresses a judgment or opinion.

    • Example: "It is raining."

  2. Non-proposition

    • Definition: A statement that cannot be true or false.

    • Example: "Close the door!"

  3. Argument

    • Definition: A set of propositions where one is claimed to follow from the others.

    • Example: "All humans are mortal. Socrates is a human. Therefore, Socrates is mortal."

  4. Non-argument

    • Definition: A statement or group of statements that do not aim to support a conclusion.

    • Example: "I like apples."

  5. Premise

    • Definition: A proposition that provides support for a conclusion.

    • Example: "If it rains, the ground will be wet."

  6. Conclusion

    • Definition: The proposition that follows from the premises.

    • Example: "Therefore, the ground is wet."

Types of Arguments

  1. Deductive Argument

    • Definition: An argument where the conclusion necessarily follows from the premises.

    • Example: "All birds have feathers. A sparrow is a bird. Therefore, a sparrow has feathers."

  2. Inductive Argument

    • Definition: An argument where the conclusion is likely based on the premises.

    • Example: "The sun has risen in the east every day so far. Therefore, the sun will rise in the east tomorrow."

  3. Valid/Invalid

    • Definition: Valid if the conclusion logically follows from the premises; invalid if it does not.

    • Example: Valid: "If it rains, the ground is wet. It rains. Therefore, the ground is wet." Invalid: "If it rains, the ground is wet. The ground is wet. Therefore, it rains."

  4. Sound/Unsound

    • Definition: Sound if it is valid and its premises are true; unsound if it is not.

    • Example: Sound: "All mammals are warm-blooded. A whale is a mammal. Therefore, a whale is warm-blooded." Unsound: "All cats are black. My cat is black. Therefore, all cats are my cat."

  5. Strong/Weak

    • Definition: Strong if the premises provide good support for the conclusion; weak if they do not.

    • Example: Strong: "Most swans are white. Therefore, the next swan I see will likely be white." Weak: "My friend has a red car. Therefore, all cars must be red."

  6. Cogent/Uncogent

    • Definition: Cogent if it is strong and has true premises; uncogent if it is not.

    • Example: Cogent: "90% of surveyed students prefer online classes. Therefore, most students prefer online classes." Uncogent: "My uncle won the lottery. Therefore, everyone can win the lottery."

Formal/Informal Fallacies

  1. Informal Fallacy

    • Definition: An argument that is logically unsound for lack of well-grounded premises.

    • Example: "You shouldn't listen to her argument about climate change; she's not a scientist."

  2. Formal Fallacy

    • Definition: An error in the argument's form or structure.

    • Example: "All cats are animals. All dogs are animals. Therefore, all cats are dogs."

  3. Antecedent

    • Definition: The first part of a conditional statement.

    • Example: In "If it rains, then the ground is wet," "it rains" is the antecedent.

  4. Consequent

    • Definition: The second part of a conditional statement.

    • Example: In "If it rains, then the ground is wet," "the ground is wet" is the consequent.

  5. Modus Ponens

    • Definition: A valid form of argument where if "P implies Q" is true and P is true, then Q is true.

    • Example: "If it is a dog, then it barks. It is a dog. Therefore, it barks."

  6. Modus Tollens

    • Definition: A valid form of argument where if "P implies Q" is true and Q is false, then P is false.

    • Example: "If it is a dog, then it barks. It does not bark. Therefore, it is not a dog."

  7. Affirming the Consequent

    • Definition: A formal fallacy where the consequent is affirmed, leading to an invalid conclusion.

    • Example: "If it rains, the ground is wet. The ground is wet. Therefore, it rained."

  8. Denying the Antecedent

    • Definition: A formal fallacy where the antecedent is denied, leading to an invalid conclusion.

    • Example: "If it rains, the ground is wet. It did not rain. Therefore, the ground is not wet."

  9. The Fallacy Fallacy

    • Definition: Assuming that if an argument contains a fallacy, its conclusion must be false.

    • Example: "You used a straw man argument; therefore, your conclusion is wrong."

Section 2: Key Concepts

  1. Credibility of an Information Source

    • Definition: The quality of being trusted and believed in.

    • Example: A peer-reviewed journal is considered a credible source.

  2. Reliability of an Information Source

    • Definition: The consistency of a source in providing accurate information.

    • Example: A news outlet that consistently reports facts accurately is reliable.

Section 3: Types of Biases

  1. Cognitive Bias

    • Definition: Systematic patterns of deviation from norm or rationality in judgment.

    • Example: Overconfidence bias leads individuals to overestimate their knowledge.

  2. Confirmation Bias

    • Definition: The tendency to search for, interpret, and remember information that confirms one's preconceptions.

    • Example: Only reading news articles that support one's political views.

  3. Representativeness Bias

    • Definition: Judging the probability of an event based on how much it resembles a typical case.

    • Example: Assuming a coin toss will yield heads because the previous tosses were all heads.

  4. Anchoring and Adjustment Bias

    • Definition: Relying too heavily on the first piece of information encountered (the "anchor") when making decisions.

    • Example: If the first price seen for a car is $30,000, subsequent prices will be judged in relation to that.

  5. Availability Bias

    • Definition: Overestimating the importance of information readily available.

    • Example: Believing airplane travel is more dangerous than car travel after hearing about a plane crash.

  6. Selection Bias

    • Definition: A distortion of statistical analysis results due to the method of collecting samples.

    • Example: Surveying only people who visit a particular website may not provide a representative sample.

  7. Heuristic

    • Definition: A simple, efficient rule used to form judgments and make decisions.

    • Example: Using the "rule of thumb" to estimate costs.

  8. Principle of Charity

    • Definition: The practice of interpreting a speaker's statements in the most rational way possible.

    • Example: Assuming the best intentions behind an opponent's argument.

Section 4: Argument Mapping Terms/Concepts

  1. Direct Support

    • Definition: When a premise directly supports a conclusion.

    • Example: "It is raining. Therefore, the ground is wet."

  2. Indirect Support

    • Definition: When a premise supports a conclusion through another premise.

    • Example: "If it rains, the ground will be wet. It is raining. Therefore, the ground is wet."

  3. Independent Support

    • Definition: When two premises independently support the same conclusion.

    • Example: "It is raining. It is cloudy. Therefore, it is likely to rain."

  4. Conjoint Support

    • Definition: When two or more premises work together to support a conclusion.

    • Example: "It is raining, and it is cloudy. Therefore, the ground is wet."

  5. Hidden Assumptions

    • Definition: Unstated beliefs that are necessary for an argument to hold.

    • Example: "Everyone should exercise." (Assuming everyone values health.)

Informal Fallacies from Section 4

Fallacies of Relevance

  1. Ad Hominem

    • Definition: Attacking the person making the argument rather than the argument itself.

    • Example: "You can't trust John's opinion on climate change; he's not a scientist."

  2. Genetic Fallacy

    • Definition: Judging something based on its origin rather than its current meaning or context.

    • Example: "You shouldn't listen to that theory; it originated from a disreputable source."

  3. Straw Figure

    • Definition: Misrepresenting someone's argument to make it easier to attack.

    • Example: "People who support environmental regulations want to shut down all factories."

  4. Red Herring

    • Definition: Introducing irrelevant information to distract from the argument.

    • Example: "Why worry about climate change when there are so many homeless people?"

  5. Appeal to Authority

    • Definition: Claiming something is true because an authority says so, without further evidence.

    • Example: "A famous actor believes in this diet; therefore, it must be good."

  6. Appeal to Force

    • Definition: Using threats to support an argument.

    • Example: "You should agree with my position; otherwise, you’ll lose your job."

  7. Appeal to Popularity

    • Definition: Claiming something is true because many people believe it.

    • Example: "Everyone believes in this conspiracy theory, so it must be true."

  8. Appeal to Consequences

    • Definition: Arguing that a belief is true or false based on the consequences of accepting it.

    • Example: "If we accept this theory, it means we must change our lifestyle, which is difficult."

  9. Equivocation

    • Definition: Using ambiguous language to mislead or misrepresent the truth.

    • Example: "A feather is light. What is light cannot be dark. Therefore, a feather cannot be dark."

Fallacies of Weak Induction

  1. Appeal to Ignorance

    • Definition: Claiming something is true because it has not been proven false.

    • Example: "No one has proven that aliens don't exist, so they must exist."

  2. Slippery Slope

    • Definition: Arguing that a small first step will inevitably lead to a chain of related events.

    • Example: "If we allow students to redo tests, soon they will expect to redo every assignment."

  3. Texas Sharpshooter

    • Definition: Cherry-picking data to suit an argument while ignoring data that contradicts it.

    • Example: "This study shows that our product is the best, ignoring studies that show otherwise."

  4. Post Hoc

    • Definition: Assuming that because one event followed another, it was caused by it.

    • Example: "I wore my lucky socks, and we won the game. My socks caused the win."

  5. Hasty Generalization

    • Definition: Making a conclusion based on insufficient evidence.

    • Example: "My two friends from that city are rude; therefore, everyone from that city is rude."

Fallacies of Presumption

  1. False Dilemma

    • Definition: Presenting two options as the only possibilities when more exist.

    • Example: "You either support this law, or you don't care about the environment."

  2. Begging the Question

    • Definition: Assuming the conclusion within the premises.

    • Example: "Freedom of speech is important because people should be able to speak freely."

  3. Burden of Proof Shifting

    • Definition: Placing the burden of proof on the wrong party.

    • Example: "You can't prove that ghosts don't exist, so they must be real."