  In this paper we propose a new perspective on the evolution and history of
the idea of mathematical proof. Proofs will be studied at three levels:
syntactical, semantical and pragmatical. Computer-assisted proofs will be give
a special attention. Finally, in a highly speculative part, we will anticipate
the evolution of proofs under the assumption that the quantum computer will
materialize. We will argue that there is little `intrinsic' difference between
traditional and `unconventional' types of proofs.
