November 17

Tom and Jim arrive a little early, before their own selves leave for the past. It seems an embarrassing situation, although no one knows why. Appropriately, the Jim they find has hair four inches long.

Putting their (four) heads together, they realized there is no paradox. The original Jim and Tom have been visiting not their past but the past of an alternative universe. After all, in their own past, they were never visited! Are they back now in their old universe? That's difficult to say. There are two Jims, two Toms, and two Infundibulae.

Jim 1 (our Jim) suggests that they now have a good opportunity to investigate counterfactual conditionals.

Click here.