# How to train humans to think in 4D?

There are well-known procedures for tricking human brains into assigning 3-dimensional perspective to 2D images. Some, like 3D glasses in a theater, work without effort, while others, like the stereogram of a galloping horse below, require some training and many people cannot do it at all:

We have a good mathematical understanding of 4D, and we routinely use computers to handle calculations in N-dimensional spaces. The problem is that our brain is adapted to create a 3D pseudoemulation. If you think about it, it's created by neurons spiking: nothing intrinsically 3D about it, rather us Earth-mammals adapted to use 3D because it's useful in a 3D environment.

Now I want to be in a place where a human girl, aged about 12, is able to "see" in 4D. More specifically, I want her to achieve 4D perspective on a 3D object. Assume that a device exists to grant that information to her if she can understand it. It may require effort, like the stereogram, work for a limited 'volume', and she may only be able to sustain it for a brief time (or it may come as natural as breathing).

I know of no human who claims to be able to do this, so this poses a bit of a problem. While it may come down to the wiring of our brain, I'm trying to think of a training program (for the child or even for the infant she once was if we want to take advantage of extra neuroplasticity of newborns) that would engender and boost this ability. I'm thinking computer simulations, minor brain surgery, etc.

How could we train/modify people to see in 4D?

• I suppose we'd need to first understand what 4D is. Imagine you're a 2D creature, living on a sheet of paper. That paper is your entire world, you cannot comprehend anything living outside of it. Now, a baseball pierces through the paper. What do you see? A dot that appears out of nowhere, that then grows larger and larger until it starts shrinking and disappears entirely. Did you understand what 3D is? Can you imagine it? Chances are, you still have no clue what 3D is. And that's how 4D is like for us. – Nolonar Sep 19 '15 at 10:29
• Don't we think in 4 dimensions already? Three spacial dimensions plus time. – Steve Bird Sep 19 '15 at 10:34
• We have a good mathematical understanding of 4D, and we routinely use computers to handle calculations in N-dimensional spaces. The problem is that our brain is adapted to create a 3D pseudoemulation. However, there is nothing to say that our mind software should only be capable of working with 3D. After all, it's just some neurons firing. I would like to tweak that software to work for 4D. – Serban Tanasa Sep 19 '15 at 10:34
• You may be interested in this web site and this YouTube playlist. – celtschk Sep 19 '15 at 11:10
• Aside from what Steve Bird commented above: What is the purpose of four-dimensional rather than three-dimensional thinking? What is the gain for the individual? It's easy to say "it's just one more dimension", but why? Can you give a reasonably concrete example where such an ability would be beneficial? That might make the question easier to answer. – a CVn Sep 19 '15 at 13:02