7.6. Why the Truth Can Never Be Proven

7.6. Why the Truth Can Never Be Proven

A famous philosophical thought experiment shows it’s impossible to prove anything to be true.

In philosophy, there’s a famous thought experiment.

It’s called the “Münchhausen trilemma,” and it shows that it’s impossible to prove anything to be true!

That’s because, whenever you offer proof that something is true, the “proof” that you offer needs to be proven too.

The “trilemma” shows that there are only three ways this continuous process of providing proof can resolve itself…and none of them end successfully!

The first way is infinite regression.

That’s when you offer proof…but then you have to offer proof of the first proof…and then offer proof of the second proof…and so on.

This goes on indefinitely, because there’s no point at which the process can stop and be definitively proven. Every proof you offer just requires more proof to support it.

The second outcome is when you get stuck in a loop, a circular argument.

That’s what happens when you decide “the sky is blue” because you’ve defined “the sky” to be one thing, and “blue” to be another thing, and therefore it’s correct to say: “the sky is blue.”

But that doesn’t constitute proof of anything.

You just made it true, through the way you defined the words.

You might as well have said, “The sky is blue, because the sky is blue.”

You’ve created a closed loop, in which each of the parts of your “argument” support each other…but the loop itself doesn’t have any solid ground to stand on.

Finally, the third possible outcome is when you get to a point where you either can’t—or won’t—go any further with your proofs.

This happens a lot. It’s the point at which people usually say snarky things like: “I’m entitled to my opinion,” or “we’ll have to agree to disagree,” or they just quit arguing with you altogether.

It’s also what happens when you try to prove the sky is blue scientifically, by proving how sunlight is scattered in the atmosphere, and how our eyes pick up this information.

But if you look closely, you’ll realize science can’t actually go any further than this.

There are other possible, unprovable explanations. You can’t disprove, for example, that we aren’t in a computer simulation, and we just think there’s a blue sky out there.

Science is dependent upon axioms and assumptions, just like any other system of knowledge. It has its limits.

In short, the trilemma shows that if you don’t get stuck (1) proving things to infinity, or (2) in a circular argument…eventually you run into (3) some premise, assumption, or conclusion that can’t be proven.

And in none of those situations do you end up with definitively proven knowledge!

This trilemma isn’t a new argument.

It’s been around for thousands of years!

Why isn’t it better known?

Because we don’t like the implication!

We want to believe we can prove things.

We don’t want to believe that our thoughts are just crude, fallible shortcuts, inevitably riddled with omissions, oversimplifications, distortions, and inaccuracies.

But they are.

It’s not a tragedy to admit this. In fact, it’s pretty humbling and liberating.

We can still prove things are false. But if we accept we can’t prove things to be true, maybe we can finally stop killing each other over our ideas of “truth.”


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