<blockquote>It is left to the reader to decide that these two statements both say the same thing. What they say is: given any collection of sets, however large, we can pick one element from each set in the collection. It bothers some people because it asserts the existence of a set (...) without giving enough information to determine that set uniquely (by applying a finite number of rules), and it is the ''only'' formal set-theoretic axiom which does this. For this reason it is customary to mention the axiom of choice whenever it is used. It need not be used if the number of sets is finite.<ref>[http://books.google.com/books?id=-o8xJQ7Ag2cC&printsec=frontcover#PPA9,M1 Page 9 of "General Topology"]</ref></blockquote> | <blockquote>It is left to the reader to decide that these two statements both say the same thing. What they say is: given any collection of sets, however large, we can pick one element from each set in the collection. It bothers some people because it asserts the existence of a set (...) without giving enough information to determine that set uniquely (by applying a finite number of rules), and it is the ''only'' formal set-theoretic axiom which does this. For this reason it is customary to mention the axiom of choice whenever it is used. It need not be used if the number of sets is finite.<ref>[http://books.google.com/books?id=-o8xJQ7Ag2cC&printsec=frontcover#PPA9,M1 Page 9 of "General Topology"]</ref></blockquote> |