GuyRule #157.3: Toilet Seat Rule
When finished urinating in a toilet that will be used by a woman, that you hope to have sex with, always put down the seat and the lid! This shows her that, 1) you care and, 2) it avoids the potentially fatal (as in she won't let you have sex with her) argument over whether you should put the seat down or she should put the seat up. It also puts the responsibilty on her to put the toilet lid down when she is finished. Why should her responsibilties be any less than ours? This is a more highly evolved argument and clearly puts us (guys) on a higher morale plane, as it should be.
This rule does not apply when you are a guest in a single guy's home, but it does apply in a guy's home that has a woman, that he wants to have sex with, living in it. -Jack Sampson