That difference is somewhat subtle and I had to read the description in the sibling comment to understand it. I would have welcomed a correction from somone I w

That difference is somewhat subtle and I had to read the description in the sibling comment to understand it. I would have welcomed a correction from somone I was interviewing. On a side note, the founders of Google once tried to explain recursion and idempotence to Terry Gross on NPR. It's pretty amusing. It starts at 13:45 into the interview here: http://www.npr.org/2003/10/14/167643282/google-founders-larry-page-and-sergey-brin-part-2 http://www.npr.org/2003/10/14/167643282/google-founders-larr...