Not all moths

I host a quiz night in our local micropub (it's cosy). Recently, in the 'insects' round, I asked whether insects are warm- or cold-blooded. They are cold-blooded, of course (this is not a technical term: they are actually ectothermic, which means they don't regulate their body temperature internally). One quizzer challenged me, because there are in fact three species of moth (out of maybe 10 million species of insect - we don't know exactly) that are warm-blooded.

Leaving aside the fact that rounding this off to, say, 3 significant figures is 0.00%, we have a question of genericity. Now, either my statement 'insects are cold-blooded' is an absolute statement meaning 'all insects are cold-blooded', in which case a single warm-blooded insect is enough to prove it wrong, or it's a generic statement: 'insects in general are cold-blooded'. I meant the latter, of course, and in the context of a quiz question where two options are given, this should be clear. One of the things Steven Pinker said, actually, was that to avoid the hedging ('almost', 'in general', etc) you find in bad prose, you should allow your reader to assume the generic interpretation. In academic writing there is a place for the precision afforded by hedging, but for much other writing I agree.

There's limits though. While researching my quiz, I read the supposed fact that 'babies are born with blue eyes'. That, I thought, was astonishing. It turned out that what the author meant was 'white babies who will have blue, green, hazel or grey eyes', not 'babies in general' - there is a very high proportion of babies in the world who have dark brown eyes, and are not born with blue eyes. If you're going to make generic statements you do have to be clear about what the universe of discourse is and your generic statement has to actually apply to the majority of things in it. (In this case, the author had made the very easy mistake of forgetting that not everyone is exactly like them.)

Another of my quizzers challenged another question. In the picture round I had asked for the name of the species of fish pictured. One was a goldfish, and the team had written 'carp'. I didn't allow this, and the challenger wanted to know why, when a goldfish is a carp. It's true that goldfish are carp, but not all carp are goldfish. 'Goldfish' is therefore a hyponym of 'carp' (and 'carp' is a hypernym of 'goldfish').

I am clearly not strict enough with my quizzers. If I keep blogging about their complaints perhaps they'll stop.