I am lucky enough to still be a friend of my first history supervisor, who taught me at Magdalene back in 1987.

If you'd told my 18-year-old self that we'd be friends more than 30 years later, he would have been surprised. Our relationship did not start well.

No one explained when I came up that clues were to be found in the way people’s names were beautifully hand-painted above the different room doors.

Mine simply said ‘MD MacConnol.’ My room was the bedroom of what had been a grand set in the Lutyens Building. The living room, across a tiny corridor, said ‘Mr George Garnett’. ‘Mr’ I thought, that must just be like being a third year.

That suspicion was reinforced before the term started when I saw George striding across the courtyard to his room. He was about 15 minutes older than me and dressed with a disdain for convention. I later discovered he had a pink inflatable pterodactyl hanging in his room and there was something of the grounded pterodactyl in the way he moved and looked at you.

Imagine my surprise when I discovered that as a post-grad he was actually on the side of the dons, not the students, and more than that, he was to be my teacher of Anglo-Saxon and Norman history (and later my Director of Studies)?

The first supervision itself, one where I actually went through an essay with him, also didn't bode well for the long-term.

As I settled myself into an alarmingly low-slung armchair and was offered black coffee, complete with grounds from a teapot, George said: “You’ve had a lot of friends over this week. That will need to stop.”

The next hour, a one-to-one session, was probably the most gruelling and forensic demolition of anything I have ever created. George wasn’t nasty, he was just unforgiving. And as the weeks went by, he didn’t let up. I still remember his description of my essay on the rule of Aethelstan: “This reads like a second-rate opera score.” Socratic dialogue is an understatement.

I am no masochist, but for all this, I am tremendously grateful to both him and the Cambridge system. After the initial shock, I leamed a few key things. To not be co wed, to raise my game, and to argue back. They have stood me in good stead for the rest of my life. There have been plenty of times in my career when put on the spot, I have turned to the skills I learned thanks to George.

Now, with daughters myself at other great universities (Durham and Birmingham), I realise how special this Cambridge experience was and is. The investment the University makes in enabling individual supervisions is near unique. It’s something at the heart of what makes education at Cambridge different.

Cambridge is of course a multi-coloured dreamcoat of wonderful experiences that make me want to support it: the friendships, the Colleges, the extra-curricular options, the lectures.

But at its heart, when asked why I became a volunteer, my mind was drawn back to George, his coffee and his pterodactyl. Educational opportunities like that are worth fighting for.