The Garden of the Blind

One of my favorite games is called “Six Degrees of Bacon” (or some variant of that). It is played by naming any person who has appeared in a motion picture, and then connecting them through co-stars to Kevin Bacon. For example, Kevin Costner was in Robin Hood: Prince of Thieves with Morgan Freeman, who was in The Shawshank Redemption with Tim Robbins, who was in Mystic River with Kevin Bacon. These paths are generally not unique (for example, Kevin Costner->Mary McDonnell (Dances With Wolves)->David Straithairn (Sneakers)->Kevin Bacon (The River Wild) also makes the connection in three steps) (also fun is the chain with three Kevins: Kevin Costner->Kevin Kline (Silverado)->Demi Moore (The Hunchback of Notre Dame)->Kevin Bacon (A Few Good Men), or Demi could be replaced by Tom Hulce->Kevin Bacon (Animal House)), and the challenge is in getting the chain shorter than a given number of links (officially they should be 6 steps or less, but in practice it’s usually desirable to get a chain in three or fewer links).

This game is fun for several reasons. First, it takes a lot of movie trivia, and I like both movies and trivia. Second, it’s a challenging optimization problem that is quite rewarding when done well. I don’t think that this would be universally true of all similar games. The Kevin Bacon game works because it has two very important properties. The scope of possible connections, while very, very large, is small enough to be manageable, and the relevant information is widely available. This has allowed the game to be entirely analyzed, and for a search engine to play it automatically. Fortunately, this doesn’t ruin it for casual players who just want to test their memory.

By contrast, the general Six Degrees of Separation doesn’t work. It is really just a theory that any two people, anywhere on the planet, can be connected by no more than a series of 6 mutual acquaintances. For example, I belong to a message board with a member from Sri Lanka (or somewhere else, I’m making up the rest of these so it doesn’t matter) who may have met someone from Morocco who buys carpets from a supplier in Chad who asked for directions from a villager in a remote village who’s nephew was just born last week. The problem here is that there are an insane number of connections (certainly more than trillions), and they are poorly known. I may know all of the connections for myself (which I don’t), but it is almost in the definition of the game that I can’t know any of the further connections.

Actually, no one really tries to play the general game (established variants do exist to connect baseball players or other athletes, or to connect two arbitrary actors), but occasionally my mother will ask me to try to connect some relative to Kevin Bacon (answer: they didn’t appear in any films, and therefore cannot be connected to Kevin Bacon).