Thales famously said: "Water is the origin of all things, and all things end in water." He denied the view that God created everything and created the correct path to understand the world from the world itself. In science, he advocated rationality and was not satisfied with the special understanding of intuition and perceptuality, but advocated abstract rational general knowledge. For example, the fact that the two base angles of an isosceles triangle are equal does not refer to individual isosceles triangles that we can draw, but to "all" isosceles triangles. This requires demonstration and reasoning to ensure the correctness of mathematical propositions and to make mathematics theoretically rigorous and widely applicable.

Thales's active advocacy laid the foundation for Pythagoras to create rational mathematics