rotational logic

FP Ramsey makes the following observation in the 1927 “Symposium: Facts and Propositions”: We might, for instance, express negation not by inserting a word “not,” but by writing what we negate upside down.

There’s two possible talks to give, and I’ll decide based on a vote by those present. First, I can discuss Local Fact Change logic. This talk would assume familiarity with modal logic, and cover a number of interesting and well thought through results.