I argue that Frege Problems in thought are best modeled using graph-theoretic machinery; and that these problems can arise even when subjects associate all the same qualitative properties to the object they’re thinking of twice. I compare the proposed treatment to similar ideas by Heck, Ninan, Recanati, Kamp and Asher, Fodor, and others.

This work analyzes Peter Geach's problem of intentional identity, viz. adequately formalizing the sentence "Hob thinks a witch has blighted Bob's mare and Nob wonders whether she killed Cob's sow" and other sentences like it. First, Geach's problem is presented, and then Geach's original formalization proposals, and his own reasons for rejecting them, are presented and discussed. Next, the solutions proposed by various philosophers and linguists are presented and analyzed in detail. All are shown to be either inadequate or incomplete. (...) As a result, the standard objections to one particular solution, the pronoun of laziness solution, are re-examined and shown to have problematic consequences. Finally, a modified pronoun of laziness solution that avoids the standard objections is presented and defended. (shrink)