Basically your friends are not your friends for any particular reason. They are your friends for no particular reason. The job you do, the family you have, the way you vote, the major achievements and blunders of your life, your religious convictions or lack of them, are all somehow set off to one side when the two of you get together.
If you are old friends, you know all those things about each other and a lot more besides, but they are beside the point. Even if you talk about them, they are beside the point. Stripped, humanly speaking, to the bare essentials, you are yourselves the point. The usual distinctions of older-younger, richer-poorer, smarter-dumber, male-female even, cease to matter. You meet with a clean slate every time, and you meet on equal terms. Anything may come of it or nothing may. That doesn't matter either. Only the meeting matters.
Noel Butler was such a friend. And today would've been his birthday which we never celebrated. We didn't know each other's birthday. Ours wasn't that kind of friendship. Our friendship was mainly an epistolary friendship which lasted for almost thirty years and was a meeting of the minds, rekindled when we met again in person, either in Wewak in New Guinea where Noel lived, or in one of my many corners of the world known to Noel only from the postage stamps on my many letters to him.