Retention

I am amazed how some people can retain knowledge. Like for instance G can talk about stuff with a lot of knowledge that I may have learned about at one time or another, but have since forgotten - you know the saying, "If you don't use it, you lose it?" Well that is me. But not G. You can bring up almost any subject and he will know something about it - in great depth. How does he do that?

Man, the only thing that I can retain, and with great success, is water.