You are in a disreputable bar and decide to order a ten dollar drink. A particularly slinky character asks to make a bet over your drink. This is his proposal:
"I will place a flat peice of glass over the top of your drink (so it seals and nothing can go in or out while glass is in position) and proceed to drink your drink without moving or touching either glass or glass. I think a five dollar wager is about right."
Assuming there is not trickery involved, is this a bet you should take?
I wouldn't take the bet; for if I do, the slinky guy merely removes the flat piece of glass and drinks my drink, and then pays me off $5 for losing the bet. He gains a ten dollar drink, for which he only pays five.