The limits of factive knowability

Famously, the Church-Fitch paradox of knowability is a deductive argument from the thesis that all truths are knowable to the conclusion that all truths are known. In the argument knowability is analyzed in terms of having the counterfactual possibility to know, which is a non-factive notion, i.e., a notion that does not imply truth. Several philosophers claim that, if the knowability thesis is reformulated with the help of factive concepts of knowability, then omniscience can be avoided. A factive notion of knowability is one that implies truth. In this project we will research different notions of factive knowability, relating these to non-factive epistemic -ability concepts, while taking into account general theories of so-called 'blankables' (e.g., 'thinkable'). Where needed, formal models will be constructed. Then we will investigate whether actual omniscience and possible omniscience, i.e., the existence of a 'state' at which every truth is known, can be avoided. The aim is to gain a deeper understanding of the limits of knowledge.