The Ravens Paradox Is A Confusing Philosophical Conundrum

The following story is about a raven and an apple. It seems quite simple and easy to follow, but it only gets more complicated from here. In this story, the apple is green, and the raven is black. Because this apple is green, we can conclude that all ravens are black.

Where did we lose you? This is the paradox of the raven, a philosophical paradox that looks at how conclusions can be confirmed by positive instances. Let's try it again, slower this time...

The raven paradox is also known as Hempel's paradox, as it was introduced by the logician Carl Gustav Hempel in the 1940s. Let's start at the beginning: you have two propositions. First, you are told all ravens are black. Next, you're told all nonblack things are nonravens. The evidence you have to support these propositions is a raven that is indeed black, and an apple that is neither black nor a raven. If we're able to logically conclude that all nonblack things are nonravens by looking at a black raven, then we should be able to conclude that all ravens are black just by looking at a green apple. Obviously, this logic doesn't work if you just show someone a green apple. But in this exercise, it should make perfect sense. And that's why it's a paradox. The paradox has real-world applications as well. Learn more about that in the video below.

The Paradox Of The Ravens

Can you follow what Hempel is saying?

"All Ravens Are Black"

Here's a simpler explanation of the raven's paradox.

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10 Mind-Bending Paradoxes

Welp, nothing makes sense...

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Key Facts In This Video

  1. The friendship paradox occurs because a handful of popular people are part of more social networks. 03:44

  2. The liar's paradox can be summed up in one sentence: "Everything I say is a lie." 05:42

  3. The paradox of the specious present asks if anything can truly be considered to exist in the present. 10:52

Written by Curiosity Staff October 26, 2016