On John McKay

John Keith Stuart McKay: 1939-2022

John McKay’s groundbreaking contributions include Moonshine, the A-D-E correspondence and the McKay conjecture on group representations. He was rare among mathematicians, in that he observed the vista of mathematics from afar and saw hidden connections, some of which at first seemed preposterous. His ability to unify mathematics reminds us to cultivate broad interests, at a time when specialisation is the norm.