Well, as I have read, Erdos didn't "use speed" the way one might think most people use speed. He took the same small dose -- 5mg, IIRC -- every morning. He qu

Well, as I have read, Erdos didn't "use speed" the way one might think most people use speed. He took the same small dose -- 5mg, IIRC -- every morning. He quit to prove to a colleague that he could quit, but once that was established, as you say, he went back to his previous practice. The point is, if everyone who used psychoactive drugs did so as responsibly as Paul Erdos, there would be little reason to make them illegal.