‘“M”,’ Bob continued ‘is “the miners”, “u” is “the university teachers”, “sx” is “x has a special case”, “hxy” is “x works harder than y”, “bxy” is “x will get a bigger rise than y”, Universe of Discourse is groups of workers. Show by constructing a formal derivation that (c), (f) and (g) together imply (b). You don’t know how to do this stuff by any chance, do you?’ he asked this anonymous female hopefully. ‘My girlfriend thinks I have no brain.’

‘And is she right?’

‘Ha, ha,’ Bob said. ‘You’re quite witty, aren’t you?’

The door to the bedroom was ajar and I gave it a nudge so that it opened just wide enough for me to catch a glimpse of Bob lazing naked amongst a tumble of empurpled sheets.

‘Brain and brain, what is brain?’ Bob said in a ridiculous voice. I nudged the door a little further until I could see the Finnegans Wake girl lying with the sheet pulled decorously up over her torso but nonetheless presumably naked also.

‘What are you talking about?’ she said in an exasperated tone.

I pushed the door wide open.

‘Arse,’ Bob said eloquently when he saw me. The Finnegans Wake girl screamed realistically.

‘It’s Star Trek,’ I said helpfully to her, ‘an episode called “Spock’s Brain”, from the third series.’ I shut the bedroom door. I couldn’t think of anything else to do.

I was about to leave when the phone rang. I picked it up and listened in silence to the voice at the other end. Finally, I said, ‘Right, I’ll tell him then.’

‘The power’s off?’ he guessed. ‘We’re out of tea? You’re leaving me?’ he added rather dejectedly.

I sighed. ‘No, none of those things. Your father’s dead.’

Poor Bob Senior, a man I hardly knew really apart from the odd conversation over the tea-table about the state of the garden or the politics of state. Nonetheless, it was I who had the tears running down my face, while Bob stared helplessly at the Finnegans Wake girl, already pulling her clothes on and heading for the door.

What a particularly bad twenty-four hours it had been.