[mabbo]

Watch the part about the slicing of 2d world looking at the 3d objects. That slice is infinitely large in both dimensions, yet it can't see the 3D objects when they aren't in the same plane.

Now apply the same analogy to our world: our 3D world is just an infinitely large 3D plane in a 4D world. When the objects aren't in our 'plane', we can't see them.

[pbhjpbhj]

See also Flatland (http://amzn.to/2qKFrOh, aff. link) which is a short novel in part about 2D shapes discovering the third dimension.

Edit: Didn't notice it was mentioned at the end of the comments, https://news.ycombinator.com/item?id=14472395, there's a free version linked from archive.org.

[mabbo]

A favorite novel of mine actually! Hard to believe that it was written in the 1800s, yet still Abbott understood the 4th dimension better than most people today.

[fao_]

> Hard to believe that it was written in the 1800s

Aside from all the misogyny and the style of writing, you mean?

[mabbo]

It was the 1800s. I'm sure that 150 years from now, everything you and I are writing now will be offensive in ways we don't understand today.

[throwaway135634]

To be fair I think the misogyny was satirical

[fao_]

You obviously know that it wasn't, otherwise you wouldn't have created that throwaway.