Talk:Set

This article could use an introductory level definition, along with the definition of elements of a set, and how to count them.--MCrawford 02:55, 5 August 2006 (EDT)

I don't think that's a very good explanation of why the power set has the size it does -- there is a much more direct counting argument to arrive at that result, and as currently presented it's totally unclear what that sum has to do with anything. Also, I think that explanation would be better in the article on power set rather than here. --JBL 14:10, 12 November 2006 (EST)