"You Know What They Say..."

Whenever someone is imparting some piece of wisdom, the mysterious "they" is always referenced.

If you have no idea what I'm talking about:

"They say you should wait half an hour after eating before going swimming."
"They say a bird in the hand is worth two in the bush."
"You know what they say: a rolling stone gathers no moss."

But who is this "they"? Of course someone came around once and first said these things, but then wouldn't it make sense to say "You know what [insert inventor of statement] says..." or even "You know what he/she says..."

I like to imagine the infamous "they" as a group of wise gentlemen and ladies sitting on leather couches in a windowless room constantly repeating the world's words of wisdom. This group is the they that says all these things. They give us all wisdom so that we may better ourselves and avoid drowing by swimming too soon after we eat.

-Lauren-

Note: "they" is of no relation to the "she" that said all those things.