The chief interest of Dummett’s paper for us is his characterization of the opposition between what he calls “realism” and “anti-realism.” This distinction is laid out in the first third of the paper (pp. 239-244), with the discussion of the reality of the past in the remainder of the paper serving as an example.

The example is not an easy one—as Dummett notes when he introduces it—and we won’t have time to discuss it in detail. I would encourage you to read as much of it as you have time for. Reading at least the first couple of pages (through the middle of p. 246) will put you in a position to understand Dummett’s last paragraph (p. 258), in which he summarizes the course of his discussion of the example. The issues are filled out further with each step of the exchange he describes there.