What is Mr. Antolini talking about when he speaks of "a beautiful reciprocal arrangement"?

In the book The Catcher in the Rye by J. D. Salinger; Mr. Antolini gives us a new perspective: education is of inherent value itself, it's a way of connecting to people who feel just the same things you do.

When he talks about a reciprocal arrangement, he refers to the fact that at a certain moment, one learns about the experience and mistakes of others.

And the cycle repeats itself, when you have made your mistakes you have to return the favor by guiding someone else.

This is called "a beautiful reciprocal arrangement".