I know that Richard Dawkins is wrong about Down’s syndrome, because I know my son

No household that contains a 13-year-old boy is eternally tranquil. There had been a bit of temperament that evening, an outright refusal to go to bed, hard words for his mother and his father, and trickiest of all, an attitude that seemed to deny not only our parenthood but our humanity.

Then the dam broke, and that was better but more exhausting. Still, at last he was in bed and at peace and the world was easy again. So I poured drinks for us both and raised my glass: ‘Dawkins was right,’ I said. And my wife laughed and agreed. Thank God for jokes, eh? What would life be without ’em? So thanks to Richard Dawkins for bringing us a new one; it won’t be the last time we use it.

Because Eddie has Down’s syndrome, you see, and that’s not always easy. Of course, there are thousands of other occasions when things are quite different. I could tell you about the grass snake Eddie and I found swimming in the river as we were paddling our canoe or the banana bread we make or the walks we took on holiday in Cornwall, when we found clouded yellow butterflies every day.

I put all that in for balance — well, not exactly balance, for the good outweighs the bad as an elephant outweighs a feather — but I can’t put such stuff to Dawkins. It’s emotional, you see, not logical: ‘one of a common family of errors’. The banana bread argument is not valid in Dawkinsian terms.

OK — recap: Dawkins told a woman on Twitter that if she was knowingly pregnant with a Down’s syndrome foetus she should ‘Abort it and try again. It would be immoral to bring it into the world if you have a choice.’

Strong word, immoral. There are, as I see it, two possible arguments for using it here, though there’s also a sort of Venn diagram overlap which I’ll leave for third.