This course introduces some of the most common argument forms that use premises of the form “A or B”, “If A then B”, “All A are B” and “Some A are B”. These types of claims are introduced and discussed in the “Basic Concepts in Propositional Logic” course, and I strongly recommend you at least have access to those tutorials when going through this material.
Our goal as critical thinkers is to be able to recognize these argument forms when they appear in ordinary language, and know which forms are valid and invalid (note: the distinction between valid and invalid arguments is discussed at length in the “Basic Concepts in Logic and Argumentation” course). These forms have been studied and taught for centuries (hence the prevalence of Latin names like “modus ponens”).
Part 1: Argument Forms Using Disjunctions (A or B)
1.1 Valid forms using OR (2:42) (FREE)
1.2 Invalid forms using OR (2:42)
Part 2: Argument Forms Using Conditionals (If A then B)
2.1 Modus ponens (3:53)
2.2 Modus tollens (1:49)
2.3 Hypothetical syllogism (3:50)
2.4 Affirming the consequent (3:28) (FREE)
2.5 Denying the antecedent (3:35)
Part 3: Argument Forms Using Generalizations
3.1 Valid and invalid forms using ALL (2:41) (FREE)
3.2 Valid and invalid forms using SOME (2:08)
