Personal Growth

Meno's Paradox Says You Can't Ever Learn Anything New

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We at Curiosity are pretty enthusiastic about learning. It's kind of our thing. So when we learned about Meno's Paradox, we started freaking out. On the one hand, those of us who already knew about the paradox weren't learning anything new by reading about it, while those of us who didn't know about it had no way to say for sure if what we were reading was true. But wait, doesn't that mean that it's impossible to ever learn anything at all? Is our entire existence built on a lie?

Related Video: This Is How Your Brain Grows

Knowledge: Can't Learn With It, Can't Learn Without It

If you're not very familiar with the animals of Madagascar, you probably don't know what a tenrec is. But then again, maybe you do have some expertise in Madagascarian animals. So then let's say you actually encounter one out in the world. If you're in the first camp with the rest of us, you still won't know what a tenrec is after you see it — you'll just know that you saw something like a hedgehog wearing a yellow hoodie. And if you are already well aware that tenrecs look like Sonic's banana-colored cousin, then you didn't learn anything new by seeing one in the wild either.

This is Meno's Paradox — either you already know something, so you can't learn it, or you don't know it, so you can't verify it. It first popped up in conversation with Socrates, who phrased it like this: "A man cannot search either for what he knows or for what he does not know. He cannot search for what he knows — since he knows it, there is no need to search — nor for what he does not know, for he does not know what to look for."

Hmm. Seems to make sense. Does that mean we're out of a job?

We Falla-See the Light

Our entire worldview is spiraling into the void, but we have to say: we're pretty sure humanity has learned at least three things since Socrates' time. Like sandwiches. We didn't know what sandwiches were back then, right? So there must be some kind of loophole to the paradox.

Here's how you can get around it pretty easily. Think of the paradox as a syllogism: a type of philosophical argument where, if all the premises are true, then the conclusion has to be true as well.

Premise 1: If you know what you're looking for, inquiry is impossible.

Premise 2: If you don't know what you're looking for, inquiry is impossible.

Conclusion: Therefore, inquiry is impossible.

So here's the thing. "What you're looking for" in this sense can have more than one meaning, and it's being used in two different senses in the two premises. If "what you're looking for" means "the answer to your question," then Premise 1 is true but Premise 2 is false. And if "what you're looking for" means "the question you need to ask", then Premise 2 is true but Premise 1 is false.

This is the fallacy of equivocation, wherein the same term is used for two different concepts. If your geologist friend says "I'm a big rock fan," and you say "You must love KISS," then you've just committed the fallacy of equivocation. So cheer up, Curiosity fans (and, er, writers). It turns out you can learn all sorts of things after all.

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Curious about how you know anything? Try "How Do We Know?", a beginner's guide to epistemology by James K. Dew Jr. If you pick it up from Amazon, then you can also know for sure that Curiosity will get a little bit of money, too.

Written by Reuben Westmaas November 29, 2017

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