Philosophy

Syllogism is a deductive reasoning that has three elements 1) major premise, 2) minor premise and 3) conclusion. Each of these elements is made up of a sentence which has a subject and a predicate connected by a linking verb.  The major premise, written first, is the general statement. It includes the major term and the middle term. Next is the minor premise or the specific statement. It contains the minor and the middle term. The subject of the major premise becomes the predicate of the minor premise. Lastly, the conclusion is derived from the two premises. Its subject comes from the subject of the minor premise, and its predicate comes from the major premise. Only the middle term does not appear in the conclusion. Syllogism plays a role in persuasion by convincing people to believe weak or false statement to be true.

Truth and validity are usually interchanged, but they have a clear distinction from each other. Truth is dependent on ones judgement whether the idea reflects reality or not. Since judgment is expressed in propositions, it is assumed that truth (or falsity) applies only to the propositions or the sentences, and not to the argument itself. The premises or conclusion can be said to be true or false, but not the argument as a whole. On the other hand, validity (or invalidity) applies only to the argument, but not to each sentence or premises and conclusion. It refers to the interrelation among the sentences. Validity is concerned with the structure and not with the thought the sentences are referring to. It adheres to the rules of following the premises and the conclusions to show their relationship.

An argument can still be valid even though its premises or conclusion is not true. Example All wide-eyed creatures are monkeys. My friend is wide-eyed. Therefore, my friend is a monkey.  Here, the major premise and the conclusion are not true, yet the argument is still valid because it illustrates the logical relationship among the syllogistic elements.