It’s late summer in Penwith, Cornwall, and the outsiders – the “emmets” or “ants” – are in full glut. They have clogged up the A30 with their SUVs, and now they are in their £2,000-a-week holiday lets, having panic attacks at the Sennen surfing school (“I booked private lessons!”).

They are pleading for sourdough at the St Ives bakery and sulking when they cannot have it because some other emmet has taken it all. It’s exactly the same at Christmas, but with logs, not loaves.

I have lived in Penwith for 20 months and, like most converts, my strategy is to attempt to out-Cornish the Cornish in pride of where I live, which is a tumbledown farmhouse in Newlyn; to praise Cornwall more than they do; and to be angrier on its behalf than they are.

If I could take a vow, I would. Of the fact that, until 20 months ago, I was an “emmet” in a £2,000-a-week holiday let, we must not speak. I even ate at Rick Stein’s seafood restaurant in Padstow once. I wouldn’t do that now.

So here is a charge sheet against Londoners who come to Cornwall by a Londoner who came to Cornwall, for accuracy.