That was Plato and Socrates's secret

Oh, that's where I messed up. I took the thickener, not the thinkener.

a^2 + b^2 = c^2

https://en.wikipedia.org/wiki/Hindsight_bias

"Hindsight bias, also known as the knew-it-all-along phenomenon or creeping determinism, is the common tendency for people to perceive past events as having been more predictable than they were."

It's a kind of cognitive bias that assumes things that are obvious to us would be inevitably found without uncertainty, or trial and error.

I think that a "solution" could have that "so obvious" bias like you're saying. I don't think that natural phenomena necessarily has to though. I remember many ways that physics and other sciences describe how systems behave being obvious to the point I knew the lesson before it was taught (just without the correct terminology). Density, leverage, heat conduction, etc were just describing behaviors I think most people understand through experience without needing a class. We still credit a guy getting hit with an apple as the "discoverer" of gravity. He just got the clout for something everyone already knew.

That seems like a fair percentage estimate. What you're leaving out is society. The ancient Greeks, even the 99.9% dummies, were excited about philosophy and learning. Today, Joe Rogan is one of the most popular podcasts in the world and you can't throw a stick without hitting a dozen grifters proudly parroting logical fallacies while people clap. So yeah, there might be eight million people out there, but their thoughtful blog probably gets a dozen hits a month. Their world changing lecture was cancelled for being woke. Their exciting revelation they add to the conversation get overshadowed by someone yelling how great "Oh! My Balls!" was last night.

At the time, in Greece they thought of apes as monkeys without tails. They also had no reason to think those creatures were particularly bipedal. Or that there was any particular relation to humans. Aristotle was describing Baboons, which walk on all 4s. To Plato, a bird might be the only other creature that walked on two legs. It also has pink skin for what that's worth.

It's easy to forget that the foundation of knowledge we have is so incredibly vast it would be incomprehensible to the ancient Greeks. We learn in elementary school things that people wouldn't work out for centuries.

Imagine telling Diogenes that dolphins are foxes that learned to swim. Or that the giant skulls they keep finding aren't one eyed giants, but the skulls of ancient hairy elephants.

Plato was alive when Greek philosophers decided the earth was round, and it would be a few hundred years before somebody would make the first real calculation of its size.

I guess they just forgot about gorillas

We often take for granted how much information we have about the animal kingdom. Gorillas are native to central Africa; it is highly unlikely Plato ever even met somebody who had seen one. What makes Greek philosophy impressive is how much they were able to accurately describe given the incredibly limited slice of what is now “common knowledge” available to them, and how durable the methods they employed have proven when provided better priors.

Much like another wise man.

The socratic method, which, as the name suggests, he did, is about asking probing questions to expose gaps or contradictions in their knowledge which reveal their ignorance. Both to themselves and oftentimes to other's, as well. He didn't stump them with his own knowledge. He only asked questions until they stumped themselves.

He found that wisdom was found in humility. "The only true wisdom is in knowing you know nothing." That is what I paraphrased as "I dunno". Understanding that you do not and cannot know all things is a core principle of his idea of wisdom and his methodology.