Having seen the French caper flick Rififi last night, in which an alarm system is disabled with fire extinguisher foam, what are the odds that I would today read a Donald E. Westlake short story ("The Ultimate Caper: The Purloined Letter") in which an alarm system is disabled with Redi-Whip? Long odds, it seems to me. Long, long odds.

If I hadn't seen the movie last night, I doubt I would have caught that tiny joke in the Westlake story. Yet how many times have you caught a reference that you wouldn't have caught unless you'd seen, read or heard something else within a fairly short amount of time? I know it's happened to me quite often.

As uncanny as these coincidences seem, it seems to me that culture can only exist and be transmitted via a vast network of shared references. There must be a supply of these matching references that is limited only by number of nodes in our network of cultural references, a vast supply, which we only really notice when a pair of them smack us in the face, like foam defeating an alarm system. Rather than finding the coincidence usual, I tend to think that the strange thing is that we don't notice more of these coincidences. After all, they must be going on around us all the time.