Do men have more teeth than women?

The actual answer is no. Both men and women have 28-32 teeth, depending on how many wisdom teeth grow in.

But, if you’re fourth-century B.C. Greek philosopher Aristotle, the answer is a resounding, “Of course!”

“Males have more teeth than females in the case of men, sheep, goats, and swine; in the case of other animals observations have not yet been made,” he wrote in his History of Animals. He doesn’t mention who made the observation in the case of humans, but whoever it was, he didn’t do a very good job.

Still, Aristotle was so sure this was correct that he wrote it in a book without bothering to check for himself. He did this because, as 20th-century philosopher Bertrand Russell pointed out about Aristotle, “although he was twice married, it never occurred to him to verify this statement by examining his wives’ mouths.”

Sure, it might be a little awkward to tell the missus to come over here and say “Ah,” but if the philosopher had taken a minute or two to do so, followed by another minute or two for her to count his teeth, he’d have been spared this embarrassing mistake.

So, what’s the takeaway here? It’s not that Aristotle was stupid. He was probably one of the smartest people who ever lived. For well over 1,000 years, his works on biology, physics, metaphysics, poetry, politics, ethics, logic, and rhetoric were considered authoritative in their respective fields. Many of these works are still studied today, and not just as historical curiosities.

In his book Amusing Ourselves to Death, Neil Postman explains how a brilliant thinker like Aristotle could make such a seemingly foolish error: “[T]o the Greeks of Aristotle’s time, and for two thousand years afterward, scientific truth was best discovered and expressed by deducing the nature of things from a set of self-evident premises.”

Aristotle, like all fourth-century-B.C. Greeks, thought of women as defective men. Male sperm, he wrote, always tried to produce a male baby; only in cases when the sperm somehow fell short would a girl be born. With this in mind, it makes sense that Aristotle wouldn’t bother taking a gander at Mrs. Aristotle’s pearly whites. Knowledge came from deduction, not from observation. If women were deficient in other areas, then it made logical sense for them to be deficient in tooth count too.

But again, there’s a risk of drawing the wrong conclusion. The lesson here is not that the Ancient Greeks were stupid and sexist compared to us enlightened moderns. It is simply that even the most brilliant thinkers can have huge blind spots due to assumptions they’ve unconsciously absorbed from their surrounding culture.

I’m no Aristotle, and you, dear reader, probably aren’t either. It would be wise for us to stay humble and accept that many of the truths we hold to be self-evident are nothing of the kind. For example, “black lives matter” is a statement that most modern people (whatever their disagreements with the BLM organization itself may be) would see as obviously true. But the ideas underlying that claim—that every human life is equally precious, that the poor and downtrodden have a special claim on our sympathy and support, that racial intolerance is evil—would have baffled Aristotle. He took it as given that the people who made up the lower classees were inferior by nature and fit only for slavery. He considered non-Greeks to be “barbarians” (because, to Greek ears, their languages sounded like harsh gibberish: “Bar bar bar”).  

Today we condemn these ideas, but it’s important to remember that someday we’ll be the ones in the crosshairs. Many practices and ways of thinking that today seem perfectly natural to us would have been seen as absurd or monstrous 1,000 years ago, and they might well be seen the same way 1,000 years from now.

You may well ask, which ones? Perhaps it will be our obsession with screens, or our sexual mores. Maybe it will be our faith in democracy, our deference to science, or our individualistic approach to religion and spirituality. It’s hard to say. It’s like asking a fish to talk about water.

When I was a high school teacher, my students often complained about the classical curriculum. “Why do we have to learn this stuff? Who cares how many wives King Henry VIII cheated on? When are we ever going to use this?”

My response was always the same, “Why would you only want to learn things that are ‘useful’? Useful to whom?” Useful knowledge, by my students’ definition, would be knowledge that was directly applicable in the cultural, political, and economic conditions of 21st-century America. To refuse to learn anything that isn’t “useful” is to agree to only know what the powers-that-be want you to know.

Such an education makes one a cog in a machine. Aristotle distinguished between “useful” fields of study, which in his opinion were fit only for slaves, and the “liberal arts,” which made those who studied them into free men capable of questioning the assumptions that governed the world around them. I don’t share the philosopher’s contempt for productive labor, but he’s absolutely right about the second point.

As Aristotle’s misadventure in dentistry illustrates, getting beyond certain assumptions will always be a struggle, even for the smartest among us. But that doesn’t mean we should give up. By reading old, supposedly useless books, we can start to cultivate gratitude for the good things we’ve gained over the centuries, sorrow for the good things we’ve lost, and wisdom to look beyond what is, to what was, and what could be.