Wednesday, April
7th 11.30
am

→ Aula teledidattica padiglione E, DIST (via
Opera Pia 13) ←

**Alan Bundy**, School of Informatics, University of
Edinburgh (Scotland)

**Title**

What is a proof ?

**Abstract**

To those brought up in a logic-based tradition there seems to be a simple and clear definition of proof. But this is largely a 20th century invention; earlier proofs had a different nature. We will look particularly at the faulty proof of Euler's Theorem and Lakatos' rational reconstruction of the history of this proof. We will ask: how is it possible for the bugs in a faulty proof to remain undetected for several years -- even when counter-examples to it are known? How is it possible to have a proof about concepts that are only partially defined? And can we give a logic-based account of such phenomena?