Truth-Makers and Proof-Objects

Truth-makers were introduced in a very influential paper from 1984 with precisely this title by K. Mulligan, P. Simons and B. Smith, although they have their predecessors in Russell's facts, dating from the beginning of the last century. Proofs were treated as mathematical objects in Brouwer's proof of the bar theorem and, above all, in Heyting's proof interpretation of intuitionistic logic from around 1930. By a strange coincidence, the term proof-object seems to have been used for the first time in the same year as the term truth-maker, in a paper by J. Diller and A.S. Troelstra from 1984. In truth-maker theory, the truth of a proposition is defined as the existence of a truth-maker for it. Similarly, in intuitionistic logic, the truth of a proposition is defined as the existence of a proof-object for it. Thus the idea behind the introduction of truth-makers is the same as the idea behind the introduction of proof-objects, however different are the conceptual frameworks within which these ideas first arose. The purpose of the conference is to allow for exchange of ideas between, on the one hand, the ontologically oriented truth-making community and, on the other hand, the community of researchers familiar with the idea of proof-objects from their background in intuitionistic logic and type theory. The use of truth-makers and proof-objects, respectively, in the logical analysis of sentences of natural language will also be part of the conference.