cold turkey

[thamaxx]

Like all of Erdös's friends, Graham was concerned about his drug-taking. In 1979, Graham bet Erdös $500 that he couldn't stop taking amphetamines for a month. Erdös accepted the challenge, and went cold turkey for thirty days. After Graham paid up--and wrote the $500 off as a business expense--Erdös said, "You've showed me I'm not an addict. But I didn't get any work done. I'd get up in the morning and stare at a blank piece of paper. I'd have no ideas, just like an ordinary person. You've set mathematics back a month." He promptly resumed taking pills, and mathematics was the better for it.

http://www.nytimes.com/books/first/h/hoffman-man.html