# Topoi and Sets

**Date**: Monday 15 May 2017, 14:00 – 15:30**Location**: Mathematics Level 8, MALL 1 & 2, School of Mathematics**Type**: Logic, Seminars, Pure Mathematics**Cost**: Free

#### Marco Larrea, University of Leeds. Part of the postgraduate logic seminar series.

I will start by explaining the definition of an elementary topos and give some examples. Afterwards I’ll give a very informal introduction to Lawvere’s Elementary Theory of the Category of Sets (ETCS) which is an alternative first-order axiomatisation of Sets based on the theory of topoi.

**Marco Larrea**, *University of Leeds*