What Is Abstraction in Math?

What is abstraction in math? Can you define it? So I think of abstraction as being a process where you forget some details about a situation so that it becomes a little bit further away from the real life situation. The reason we do abstractions is to unify a lot of different specific situations and see what we can understand about all of them at the same time. It's quite hard for children to make that leap, because they keep counting things in front of their face,. And if it's not sufficiently guided and motivated, then some people fall off every time.