1.2.2.4.3 Plato' s Definition of Mathematics
This developed from his philosophy.
Plato believed that when we imagine a right angled triangle
we are seeing an approximation of
THE PERFECT RIGHT ANGLED TRIANGLE
which exists somewhere outside of time and space.
Thus real mathematical quantities and immutable and eternal.
The consequence of this is that
mathematicians do not invent mathematics
but
simply discover
what has always been and always will be there.
Many mathematicians today still believe this.