Karl Popper’s famous demarcation criterion — that a claim is scientific only if it can be falsified — is no longer the reigning wisdom among scholars. I’ve always liked it, however. And I’ve also liked to use it as part of a semantics of academic writing. While there’s something appealing about A.J. Ayer’s verificationism — the view that a sentence means whatever would be the case if it were true — it must be remembered that for a great many claims (especially very general ones) the truth-making “fact” would simply be too huge to verify the existence of. In that case, it’s nice to know also what would make a statement false.

This, I believe, is something that scholars are forgetting in their discussions. Indeed, their communications can hardly even be called discussions any longer because they are not probing each other’s statements often enough for how they might be false. Such a “critical” posture is in many areas taken to be impolite. But it should be a basic habit of mind. When someone claims something — or when you assert a claim yourself — you should always ask what sorts of things would demonstrate the claim’s falsity. If your interlocutor cannot imagine any fact in the world that would disprove what they are saying, then they are not making a scientific claim.

Similarly, if the claimant to knowledge refuses to even discuss sources of error, you are not dealing with a scientific claim. Or you are not being invited into a scholarly conversation.

I used to think it was Laurence Sterne who said that “Gravity is a mysterious carriage of the body invented to cover the defects of the mind.” I had let Ezra Pound tell me so. It turns out that Sterne was quoting La Rochefoucauld. I now claim that you can find the sentence in the works of both authors, with the former attributing it to an unnamed “French wit” and the latter claiming it as his own. It is possible La Rochefoucauld plagiarized it from someone else, of course. But I’m not making any claims either way. I’m claiming only that Sterne quoted Rochefoucauld. You can try (and fail) to falsify this statement by consulting Sterne’s Tristram Shandy and La Rochefoucauld’s Maxims.

Until today, I made a different claim. It was false. I claimed that Pound quoted Sterne and that Sterne wrote the original. Even a look at Sterne’s use of the sentence would falsify my assertion. Not even Sterne claims to be its author.

Too few scholars make claims about what others have said with this attitude. More gravely, they do not treat their empirical claims, or those of others, with this degree of seriousness. They don’t seem to care what would show them to be wrong. They don’t seem moved by evidence to that effect.