Published in Volume 6 (Sets and extensions in the 20th Century), North Holland, 2012, of the series “Handbook of History of Logic” edited by Dov M. Gabbay, King’s College London, UK, Akihiro Kanamori and John Woods, University of British Columbia, Vancouver, Canada,

History of Categorical Logic 1963-1977. Jean-Pierre Marquis and Gonzalo E. Reyes