Pros And Cons Of Modus Ponens

Modus ponens is a pattern of arguing that is also known as “affirming the antecedent” (cite 139). This particular type of reasoning centers on an “if _, then _” statement and an example of it would be: “(1) If you have a hundred dollars, then you can buy the basketball jersey. (2) You have a hundred dollars. (3) Therefore, you can buy the basketball jersey.” Modus ponens is also a rule of inference, such that if you follow the rule, then the argument will never be invalid. It is possible to prove that modus ponens arguments are valid rules of inference rather than just making the assumption that they are. The conditional is especially useful in propositional logic and is what can express the validity of modus ponens arguments as rules of inference.

A conditional also has the form “if _, then _” and the first blank is filled by a proposition called the antecedent and the latter is known as the consequent (cite 135). No propositional conditional can be valid if its antecedent is true and its consequent is false (cite 136). The definition of validity is that there are not possible situations where all the premises are true but the conclusion is false. Likewise, in a modus ponens argument, any situation where sentence (2) is true and sentence (1) is true, then sentence (3) has got to be true. The section of the truth table that is useful to confirm the validity of modus ponens is the first row where it is true across the board. From this, there is no question that modus ponens arguments are valid rules of inference and this specific truth table can be referenced for support of that