Is A Lap An Illusion?

The discussion "do laps exist?" has been bugging me for a week ever since I saw that damned Gilmore Girls episode. Now it's getting serious.

Think about it... your lap is there when you sit down, but it disappears when you're standing. So, does it really exist? And If you're standing, where does it go? Aaand can you touch it without utterly confirming that you're NOT only touching your legs?

I guess I could lean for "it does exist" since at any point in history and in the future, someone will be sitting down, thus, giving birth to a lap... but if there's no one there to see it, does it really exist after all?
Wait, have we already reached the "if a tree falls in the middle of the forest..." discussion level? Ufff. What do you think?

Any type of lap questions to jossbot [at] hotmail [dot] com :)