Keep in touch

I introduce a puzzle about contact and de re temporal predication in relativistic spacetime. In particular, I describe an apparent counterexample to the following principle, roughly stated: if B is never in a position to say ‘I was touching A, I am touching A, and I will be touching A’, then (time travel aside) A is never in a position to say ‘I was touching B, I am touching B, and I will be touching B’. In the case I present, the most that A is ever in a position to say is: ‘I am now touching B, but this is the only instant at which this will ever be so’. B, on the other hand, can say: ‘I was formerly touching A, I am currently touching A, and I will in the future be touching A’. (And neither object is a time traveler.)