200 likes | 350 Views
CRT Workshop. Fall 2019. Aim. Revisit and discuss three CRT concepts: Truth value Validity Inference to the Best Explanation How best to teach them?. Agenda. Short presentation about the 3 concepts Group work (3 groups) Plenary discussion Reading suggestions. Truth value.
E N D
CRT Workshop Fall 2019
Aim Revisit and discuss three CRT concepts: • Truth value • Validity • Inference to the Best Explanation How best to teach them?
Agenda • Short presentation about the 3 concepts • Group work (3 groups) • Plenary discussion • Reading suggestions
Truth value • Attribute of propositions • Classical logic (2 values only: True and False) The cat is on the mat. • Non-classical logic (Many values: Mostly True, Both) New York is a great place to live. • Probabilities, Unknowns
Problems with Truth Types of truth-claims: • Empirical (There are 25 people in this room.) • Theoretical (2 + 2 = 4) Theories of truth: • Correspondence (Claim X is true if it corresponds to facts) • Coherence (Claim X is true if it is part of a coherent set of beliefs) • Pragmatism (Claim X is true if its being true is useful for our inquiry)
Realism v. Anti-realism Two meta-approaches to truth: • Realism (There is an objective world, independent of what we think and say about it. Our claims must reflect that world.) • Anti-realism (There may be an objective world, but we can’t really know it. Our claims are expressions of our own perspective of it.)
Relativism Relativist thesis: There is no objective reality. Truth is relative to a perspective. • Problematic (self-defeating) • Applicable in a narrow set of contexts (likings and preferences) • Yet, influential among students Why students embrace relativism? Easy way out of arguing for claims; Sounds sophisticated; Relativist context
How to teach it? • Be consistent and explicit • Realism, not relativism • Stick to classical logic • If they ask for more, explain non-classical conceptions
Validity Validity: Attribute of arguments. If the premises are true, the conclusion must be true. All PowerPoint presentations are boring. This is a PowerPoint presentation. Therefore, it is boring. • A matter of structure, not of the content of words All Xsare Ys. This is an X. Therefore, this is a Y. Useful to think about validity as a mathematical (algebraic) concept.
Benefits of Validity Why is it beneficial to teach students validity? • Helps them grasp the wider context and analyze the structure of concepts and arguments • Helps them gain clarity of mind • Helps them understand the importance of relations between claims • Helps them keep track of claims • Helps them understand the unity of knowledge
Challenges to teaching Validity • Students (and faculty) dislike math and symbols • Students think that validity = good All unicorns are sexy. Donald is a unicorn. Therefore, Donald is sexy. = VALID Birds fly south in the winter. Tweety hates cold. Therefore, he flies south in the winter. = INVALID • Applicable for a limited range of claims
How to teach it? • Use symbols • Explain its mathematical nature • Use a lot of examples • Have students come up with their own examples
Inference to the Best Explanation IBE: A reasoning method aimed to overcome the limitations of inductive reasoning. Also called ‘Abductive’ method • Russell’s chicken: The chicken fed by a farmer each morning develops a theory that the feeding will continue indefinitely. The theory works every day, until… IBE tells us what is the best hypothesis we can infer from the available evidence
Why IBE is good? • Flexible, admits new evidence • Focuses on explanations, not on definitions or formulas (unless you are a Bayesian) • Applicable in a variety of contexts, can include both variables and invariables
Challenges to IBE What is best in an explanation? Focus on clear criteria: • Testability, Fruitfulness, Scope, Simplicity, Conservativeness Finding intuitive examples for students. I use Pyramids in Egypt
How to teach it? • Use a real life example • Construct a detective case study • Go through each criteria
Group work • Create one learning activity to teach Truth-value, Validity, or IBE • 15-30 minutes • Have one faculty member share it