09.18, Thursday 13 Feb 2003

Joho's Car Talk Puzzler. Prisoners, a room with two levers, sending signals. It's a really hard puzzle, fun to think about.

I can't solve it. I devised a fairly efficient system based on using one lever to signify the position of the other carried meaning, and then treating the sequence of prisoners into the switch room like a circuit. Each prisoner could generate a signal (up or down), consume a signal, or retransmit. The job of over half of the prisoners was to generate a single down signal, and retransmit all others. All but one of the rest would consume a certain number (say, 4) down signals, and then generate an up one. All others must be retransmitted. The last prisoner knows that when they've received the correct number of up signals, all prisoners have visited the room. Blah blah blah.

But, the switches are in a random position on the (random) date of the first visit! So it doesn't work. And my half-solution is hardly elegant -- not right for a puzzle answer. Alas, this is a problem with all proposed utopias. Too much top-down control, and no way to get there from here. (Incidentally, Es suggested the prisoners rush the warden and feed him to the alligators for being such a pompous arse.)