I didn’t know Stephen Hawking personally, though I often saw him around and in my early years in Cambridge (late-1960s, long before he was famous) my lab was in the same complex of buildings in Mill Lane as the department where he worked. The buildings had no ramps for wheelchair access at that time, so sometimes I or my fellow-students would help his wife to lift his (non-motorised) wheelchair up the steps into the Department of Applied Mathematics and Theoretical Physics (DAMTP).

At the time, of course, we had no idea of how important he was destined to be. The only clue was when one went into the DAMTP tea-room at 10.30am or 3.30pm (scientific departments have a tradition of gathering for morning coffee and afternoon tea) his wheelchair was always surrounded by a group of devoted graduate students, some of whom acted as his interpreter and wrote the equations on a blackboard when he was giving a lecture. It was clear then that — at least in the rarefied world of cosmologists — he was already a real celebrity.

One of those students was Nathan Myhrvold, who went on to become the Chief Technology Officer of Microsoft and a close colleague of Bill Gates. My hunch is that Nathan was the link that persuaded Gates to endow the Gates Scholars (which is Cambridge’s version of Oxford’s Rhodes Scholars scheme).

For me, the most striking moment in Hawking’s career was when he was elected to the Lucasian Professorship of Mathematics. This was the professorial chair that had once been occupied by Isaac Newton, and it seemed an appropriate recognition of the significance of Hawking’s work.

Indeed, watching Hawking in public and marvelling at his astonishing and (to me) inaccessible brilliance, it was Newton who came to mind, and the statue of him in the chapel of Trinity College, of which Wordsworth wrote in The Prelude:

And from my pillow, looking forth by light
Of moon or favouring stars, I could behold
The Antechapel where the Statue stood
Of Newton, with his prism and his silent face,
The marble index of a Mind for ever
Voyaging through strange seas of Thought, alone.