In Ice Storm, Mikey says, “Because of molecules we are connected to the outside world from our bodies. Like when you smell things, because when you smell a smell it’s not really a smell, it’s a part of the object that has come off of it — molecules. So when you smell something bad, it’s like in a way you’re eating it. This is why you should not really smell things, in the same way that you don’t eat everything in the world around you – because as a smell, it gets inside of you. So the next time you go into the bathroom after someone else has been there, remember what kinds of molecules you are in fact eating.”
For some reason, I’m forced to remember that every time I visit a visited restroom.