Compare who is older and who is younger. The math ratio formula of grade one is that the left hand hides less than the sign and the right hand hides more than the sign. The big mouth faces a large number, and the sharp mouth faces a decimal number. The big one is on the left, greater than the number, and the small one is on the left, less than the number. The greater than sign is on the left and the less than sign is on the right.

Mathematical essence

The essence of mathematics is to describe the changes in the number and relationship of structures, and to verify the methods and processes of structures and relationships. As for logic, it is more like the inherent characteristics of structure and relationship, while abstraction is the means to find the process of structure and relationship. Therefore, mathematics has stripped off all meaningless concretes in an abstract way, leaving only simple structures and relationships to explore the logic.

A long time ago, mathematics originated from the concreteness of life. At that time, it was not called mathematics, but a simple counting system. For example, natural numbers are specifically mapped, but from the beginning of rational numbers, they are divorced from reality and become artificial creation and abstraction. Now, it has completely become a pure thinking activity, completely divorced from reality, which can be said to reflect the evolution of human abstract thinking and reasoning ability, that is, the evolution of intelligence.