Salman Panahy

‘A Justification for Deduction and Its Puzzling Corollary’ (PhD in Philosophy, 2019).

This thesis examines how deduction is analytic and, at the same time, informative. The first two chapters are dedicated to the justification of deduction. This justification is circular, but not trivially circular as not every rule can be justified circularly. Moreover, deductive rules may not need suasive justification because they are not ampliative. This means that deduction adds no information to what we already had in our premises. However, there are many ways deduction can be informative. In the rest of thesis I attempted to understand the nature of information we obtain by this kind of reasoning. I suggested that the proofs we construct to prove theorems, of a certain complexity, puts us in an epistemic position that we were not in before having the proof. More specifically, I showed that concepts we need to confirm the conclusion are made in the process of proving the conclusion.

Supervisors: Professor Greg Restall, Dr Laura Schroeter