ABSTRACT
The paper gives an overview of Arthur Schopenhauer's theory of rationality. For Schopenhauer, rationality is a human faculty based on language, which, in addition to language, is primarily concerned with knowledge or philosophy of science and practical action. For Schopenhauer, language is the umbrella term under which he subsumes logic and eristics. This paper will first introduce Schopenhauer's logic and clarify its connection to the philosophy of language. This is followed by eristic dialectics, which reflects on how one can protect oneself from people who argue irrationally in a goal-oriented way. Schopenhauer's philosophy of mathematics belongs to the field of philosophy of science. Unlike many other authors of his time, Schopenhauer does not advocate a rationalist but a representationalist approach, which, however, includes a theory of rationality. Therefore, Schopenhauer's representationalist approach will finally be discussed, emphasizing its relationship to his theory of rationality.
