Grigori Mints Reductions of finite and infinite proofs Standard expansion of a finite proof d in arithmetic into an infinite proof h(d) provides normalization theorems for finite proofs of simple formulas, usually of complexity at most \Sigma_1. A slight modification of this expansion allows to normalize finite proofs of arbitrary formulas, even if the normal form contains eigenvariables. This approach extends to subsystems of analysis. It can be used to extract a set of reductions for finite proofs from cut-elimination for infinite proofs.