How Do You Know?

Most of us admit that we don’t know everything. However, we usually feel certain about some of our facts. We may think they’re obviously true, or that they’re so certain that everyone accepts them. I want to challenge this assumption.

I want to use the example of whether the earth is a sphere or some other, flat shape. I know the earth is spherical. You know it. Everyone knows it except for a few flat-earthers. I’m not hoping to convince anyone that the earth is flat. What I’m trying to do is to show that some of our most fundamental beliefs, things we accept without question, are based more on faith than on reason.

So – how do we know the world is round? Our teachers told us this, and our parents, and everyone we know. But let’s say there’s someone we’ve met – maybe from an isolated island – who has never heard that the earth is round. How can we prove it to him?

Photos? Hardly. It has always been possible to manipulate photos to make things appear that never happened. This has been going on since the beginning of photography. Sir Arthur Conan Doyle was taken in by the Cottingley Fairies back in the early 20th century. With the advent of digital photography and photographic manipulation, it is almost impossible to reliably detect fraud in a photograph. We simply can’t rely on photographic evidence.

Photographic Proof of Fairies

Well, there is the testimony of travelers who claim to have gone steadily east (or west) and continued until they arrived back where they began. If this is true, then it is good evidence that the world is round. But unfortunately, not everyone is honest. Maybe these so-called travelers were lying, or maybe they were simply confused. Someone pointed out to me that the shadow of the earth on the moon is curved, which would only happen if the earth itself were curved. Maybe so – but that might only mean that the earth is disk- shaped, flat but circular.

If you think about it, almost all of the evidence about the shape of the earth is beyond our ability to confirm. We have to take it on faith. That doesn’t mean we should reject the idea of a spherical earth. I’m pretty sure that’s its shape. But we should keep in mind that most of what we think we know is based on faith, not logic.


Author: seeker