The "Second Analytics" ("Analytica Posteriora"), created in the 4th century BC, is part of the esoteric writings of Aristotle and presents his theory of science, which includes a theory of knowledge. It examines the question of what science is and how it becomes possible. Central to Aristotle's thought is the thesis of the primacy of sensory perception, which precedes the emergence of knowledge: every instruction and every rational acquisition of knowledge arises from already existing understanding - but according to clear and demonstrable rules. The science thus defined is then divided into two complementary parts. One is the deductive derivation of statements from evident, self-evident propositions that are still considered the epitome of rigorous science today, and the other is the recognition of principles, i.e., the methodical understanding of these principles.