My latest essay (first in a little while) is now up at The Everyman, this one critiquing our tendency to insist that this, that, or the other fact ‘doesn’t matter’ by applying the analogy of detective literature.

I read a lot of detective fiction (I also write it, though I’ve written much less than I’ve read so far) and find it most beneficial to the brain. There is a lot of good philosophy in Agatha Christie.

One of the core tenets of a good mystery is that all the facts of a case must be accounted for. Usually it will be structured so as to appear superficially to bear one particular interpretation, which the ‘official’ detective in charge will swallow wholesale. In the process, there will usually be one or two small facts or features of the case that don’t fit that official narrative—a pulled out chair, an overheard splash, an inconsistent suspect. But these seem so small and trivial that the police slur over them as ‘unimportant.’

But as our detective hero will point out, it is precisely these small, seemingly trivial details that are the most important simply because they do not fit. In any case, you can’t know for sure what the truth is until you have somehow accounted for all the facts.

For instance in Evil Under the Sun, someone at a seaside hotel is overheard to have been taking a bath at about the time of the murder. It seems completely irrelevant, but it is a fact and must be accounted for. And because no one will admit to it, Monsieur Hercule Poirot deduces that, unlikely as it seems, it must be significant. Naturally, it proves one of the keys to the unravelling of the mystery.

“It is just what some people will not do,” says Poirot in Death on the Nile. “They conceive a certain theory and everything has to fit into that theory. If one little fact will not fit, they throw it aside. But it is always the facts that will not fit in that are significant.”

It should be the mantra of all good detective stories and all good philosophy alike: if a thing is, then it matters.

This sounds obvious, and it really should be, but we so often ignore it.

Read it all here.