What causes sexual thoughts?

You know what causes sexual thoughts? I'm gonna clear the air for you tonight. I'm gonna end this debate, hopefully once and for all while on this planet, 'cause outer space awaits our presence, we are better and more unique creatures than this and all eternity is our playground, so let me go ahead and clear this one issue up once and for all and let's move on to real issues. Can we? Great. Here's what causes sexual thoughts. Ready, drumroll: having a dick.

--Bill Hicks