SSH 105 Lecture Notes - Lecture 5: Deductive Reasoning, Confirmation Bias, Modus Ponens

• School: Ryerson University
• Department: Social Science and Humanities
• Course: SSH 105
• Professor: All

Document Summary

Lecture 5: second quiz is after reading week and is chapters 1-4 in the textbook. 2 ways beliefs can be irrational: motivational errors: being influenced by what we want to be true or false, rather than focusing on the relevant evidence, failing to weigh all the available evidence properly. Such as ignoring some of the available evidence. Rejecting or being excessively critical of contrary evidence: over-valuing confirming evidence (a. k. a. confirmation bias). Only looking at, or being insufficiently critical of confirming evidence: over valuing psychologically available evidence. Giving too much weight to memorable, striking or vivid evidence. Such as common misconceptions about shark attacks or air travel. Individually numbered premises and conclusions: only one premise or conclusion per line, the word therefore or the equivalent symbol before the conclusion, brackets after conclusions indicating which premises are taken to support them. Deductive arguments: a deductive argument intends to provide logically conclusive support for the conclusion.