On Friday morning, I meet my friend Nick so we can start working through Robin Hartshorne’s Algebraic Geometry together. We are both hungover. It feels like my brain is switched off—my tongue is reaching for words and not finding them. I make mistake after mistake, I am baffled by even the simplest exercise. But it’s not from the hangover, I haven’t done any maths in the four months since I graduated, and I’ve already forgotten basic definitions. Over four hours, Nick and I get through a massive two and a half pages.

‘I hate maths’, I say.