Heidegger and the logic of categorical syllogismsAccording to traditional syllogistic logic, which has its roots in Aristotle, there are four types of propositions: proposition A ("All S are P") , proposition E (“No S are P”), proposition I (“Some S are P”), and proposition O (“Some S are not P”). These propositional types represent all possible combinations of the affirmative/negative and universal/particular dichotomies. Each claims that a certain essence (the particular propositions I and O) or an entire class of essences (the universal propositions A and E), the subject or class of subjects, relates in one way or another (belongs or does not belong) to a class of essentials designated by the predicate of the proposition. The traditional, or Aristotelian, view for assessing the truth or falsity of these propositions assumes that each class denoted by a term in the subject and predicate actually exists. This allows certain conclusions to be drawn regarding the relationship between truth values ​​on different types of propositions, and these relationships are symbolized visually in a diagram called the "Traditional Square of Opposition". (These relationships are referred to as “contradictory,” “subaltern,” “contraries,” and “subcontraries.”) The modern, or Boolean, interpretation of Aristotle's syllogistic logic, however, makes no assumptions about the existence of classes designated by the terms subject and predicate of a proposition. For this reason, there are fewer conclusions that can be drawn about the relationships between the truth values ​​of different propositions. (The only relationship in the modern place of opposition is the relationship referred to as "contradictory....... middle of article......ways of thinking in the West -- metaphysical-philosophical and scientific -technology (Steiner 28) Philosophy, as it was understood until the time of Heidegger, was the heir of these traditions. It is both the cause and the heir of the. forgetting syllogistic logic, as a part of philosophy, is also both the heir and the cause of this central concern of the 20th century, and this "[obscuration] of its everyday function as a grammatical copula" (Steiner). 38) is both cause and symptom of the forgetfulness of being -- and of all the problems of the twentieth century. References Hurley, Patrick J. A Concise Introduction to Logic, Sixth Edition Belmont, CA: Wadsworth, 1997. Partridge, Eric Origins: A Short Etymological Dictionary of Modern English: Crown, 1983. , George Martin Heidegger New York: Penguin., 1978.