Abstract

This chapter focuses on one of the common fallacies in Western philosophy, 'existential fallacy'. This fallacy occurs when we erroneously suppose some class or group has members. In other words, statements may be true about classes or groups even if no members of the class or group exist. In terms of syllogistic argumentation, this is a formal fallacy in that it results when the premises are universal in quantification and the conclusion is particular. In the history of logic, the existential fallacy may be traced to dictum de omni, which refers to the principle in Aristotelian logic that whatever is said universally of a subject is said of everything that is contained under such a subject. In order to avoid this fallacy, one should look for empirical verification of the existence of whatever entity may be in question.