Although many people contributed to the study of infinity over the centuries it was Georg Cantor in the nineteenth century who established its modern development. Cantor created modern set theory and established the importance of onetoone correspondence between sets. For example he showed that the set of all integers can be put into onetoone correspondence with the set of all fractions and so these two sets have the same infinity. But he also proved the remarkable result that there are infinitely many infinities, all of different sizes.

The transcript and downloadable versions of the lecture are available from the Gresham College website: http://www.gresham.ac.uk/lecturesand...

Gresham College has offered free public lectures for over 400 years, thanks to the generosity of our supporters. There are currently over 2,500 lectures free to access. We believe that everyone should have the opportunity to learn from some of the greatest minds. To support Gresham's mission, please consider making a donation: https://gresham.ac.uk/support/