Why sluts are stupid

Woman asks:

'If I sleep with 3 men, everyone calls me a slut.  But when a man sleeps with 8 girls, everyone calls him a real man.  How come?'

Wise man replies:

'It's very simple. When one lock can be opened by 3 different keys, it's a bad lock. But when one key can open 8 different locks, we call it a master key'.