SSH105 - Critical Thinking I Exam Notes (Chapters 1-6)

7 Pages
Unlock Document

Ryerson University
Social Sciences and Humanities
SSH 105
Klaas Kraay

Critical thinking – Systematic evaluation or formulation of beliefs/statements by rational standards. • It’s systematic because it involves distinct procedures and technical methods (not just gut feelings). • It’s used to evaluate existing beliefs and to formulate new ones. • It evaluates beliefs in terms of how well they are supported by reasons Statement (claim) – An assertion that something is or is not the case. Premise A premise is a statement offered in support of a conclusion. Conclusion – A conclusion is a statement that is held to be supported by a premise or premises. Argument – An argument is a set of statements one of which (the conclusion) is taken to be supported by the remaining statements (the premises). AKA: The resulting combination of premises and a conclusion Inference – An inference is process of reasoning from a premise or premises to a conclusion, based on those premises. Two Crucial Points about Indicators: (1) They may not actually be present in arguments. (2) In arguments, premises do not always come before conclusions; conclusions do not always come after premises “Textual priority versus logical priority.” Evaluating the truth-value of premises and conclusions is distinct from evaluating the logical strength of arguments. TRUE/FALSE VALID/INVALID Deductive Arguments –A deductive argument intends to provide logically conclusive support for the conclusion. Deductive Validity – An argument is deductively valid if and only if it is not possible for the premises to be true and the conclusion false. Valid argument  Conclusion is logical based on given premise(s), REGARDLESS of trueness of premises. Soundness – An argument is sound if and only if it is (a) deductively valid and (b) all its premises are, in fact, true. Inductive Strength – An argument is inductively strong if and only if the conclusion is probably true, and Weakness given the premises. An argument is inductively weak if and only if it is not inductively strong. Cogency – An inductive argument is cogent if and only if it is (a) inductively strong and (b) all its premises are, in fact, true. Impediments to critical thinking: Category 1 impediments (stem from how we think): Self-interested – Accepting a claim solely on the grounds that it advances, or coincides with, thinking our interests. Group thinking – Peer pressure – Fallacy: an argument form that is both common and defective. • Fallacy of appeal to popularity • Fallacy of appeal to common practice • Fallacy of appeal to tradition • Genetic fallacy Stereotyping: drawing conclusions about people or groups without sufficient reasons. Three key ingredients in propositional knowledge: • Belief • Truth • Justification Realism – there are objective truths in that subject area and what these truths are does not depend upon anyone’s beliefs about them. Category 2 impediments (stem from what we think): Nihilism – There just are no truths whatsoever in that subject area. Moral nihilism: The view that moral assertions have no truth-value (are neither true nor false). Relativism – Subjective: what the truths are depends upon individuals Social: what the truths are depends upon what a (majority) society or culture believes. Skepticism – Statements have truth-values, but we don’t know what most or all of them are. Pulling it All Together (1) Each of the Category 2 impediments to critical thinking denies something about truth or knowledge (or both): (a) Nihilism (b) Relativism – subjective or social (c) Scepticism (2) All three views appear to be self-defeating if taken to be about everything. (3) In this course, we will take for granted that: – assertions/statements in many subject areas have truth-values, – these are objective, not relative to individuals or societies – in principle, these can be known. In other words, we’ll assume that realism about truth is, at the very least, the best default position in most areas. Conditional Statements A conditional statement is a statement of the form If p, then q. Examples: • If it rains, then the picnic will be cancelled. • If Jones didn’t commit the murder, the butler did. Conditionals are compound statements composed of two parts: The antecedent – what follows the word “if” The consequent – what follows the word “then” Disjunctive Statements A disjunctive statement is a statement of the form Either p or q. Examples: • Either the picnic was cancelled or it rained. • Either Jones committed the murder or the butler did. Disjunctions are compound statements composed of two parts called the disjuncts. Some valid conditional argument patterns: 1. Affirming the 2. Denying the consequent 3. Hypothetical Syllogism: antecedent (Modus (Modus Tollens): If p, then q. Ponens): If p, then q. If q, then r. If p, then q. Not q. Therefore, if p, then r. p. Therefore, not p. Therefore, q. Some invalid conditional argument patterns: 1. Denying the Antecedent: 2. Affirming the Consequent: If p, then q. If p, then q. Not p. q. Therefore, not q. Therefore, p. A valid disjunctive argument pattern: Disjunctive Syllogism (i) Either p or q. (ii) Either p or q. Not p. Not q. Therefore, q. Therefore, p. Justification - In general, to be justified, beliefs (or statements, or premises) have to be based on enough of the right kind of evidence. What kind is appropriate, and how much is enough, depends on the context. - a good rule of thumb: the higher the stakes, the more evidence is required for a belief to be justified. - in general, the more evidence we have for a claim, the more firmly we should believe it: “We should proportion our belief to the evidence.”(p.127). Some Ways a Claim Can be Justified: 1. It is true by definition. e.g. “All bachelors are unmarried adult males” 2. It is
More Less

Related notes for SSH 105

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.