As heard on The Big Bang Theory.
This physicist goes into an ice cream parlor every week and orders an ice cream sundae for himself, then offers one to the empty stool next to him. This goes on for a while until the owner finally asks him what he’s doing.
The man says, “Well, i’m a physicist. Quantum mechanics teaches us that it is possible for the matter above this stool to spontaneously turn into a beautiful woman who might accept my offer and fall in love with me.”
The owner then says, “Well, lots of single beautiful women come in here every day. Why don’t you buy an ice cream for one of them, and they might fall in love with you?”
And the physicists says, “Yeah, but what are the odds of that happening?”