A note on incongruent counterparts and verisimilitude

Abstract

COUNTERPARTS AN[) VER~S][M'/L,~TLi~)tZMy (1984) contains a mistake which ! wish to ~-ecUfy it concerns verisimilitude. What 1 said seemed intuitively right,, but iv conflicted with a logical result that had been arrived at a few years earlier, and of which I was unaware. The idea of verisimilitude does not play any positive role in my book; the mistake is whal doctors would call idiopathic, an isolated disorder rather than a symptom of a larger disorder; so I might have passed it over. BnI~ wish to, do justice to the people whose work I would have taken into account had I known about it when I was writing the book; and in aev case, the mistake and its rectification have, I believe, a certain intrinsic interest. Here is the offending passage:It is an incidental merit of the concept of incongruent counterparthood.., that it enables us to give a perfectly clear meaning to verisimilitude comparisons in one special case, namely where c, and cj are incongruent counterparts For in that case every consequence of c, has a counterpart among the consequences of q and vice versa: their consequences are in one:one correspondence. And Vsic,)> Ys(cj} must then mean that a true consequence of c, is paired with a false consequence of c~ more frequently than the converse. (pp. 238-84)