 Now, there supposedly are other dimensions, spatial dimensions. I think Ronnie asked, I don't understand why it's so hard for humans to visualize the third dimension, more than anything beyond 3D. It's because we don't have a perception of it. We don't exist in a four-dimensional world. We can try to understand what 4D looks like, and the way we understand what 4D looks like is through its shadow. Brett Slinger, 91. Thank you very much for the tier one sub. So the way we try to understand four-dimensions, four spatial dimensions, is by looking at the shadow of a four-dimensional object in 3D. So right now, like here, check this out, like I'm putting a shadow here, right? Agreed? So if I hold up a 3D object, these are all 3D, but here, let's do a pen. Not a pen, a cup. Like SAP, I got my certificate in this, right? I keep it as a member. Is this even thrown a shadow? There you go. There's a shadow of a cup. There's a shadow of a cup. Three-dimensional object. This is what the shadow of the cup looks like, right? Let me see if I can do it here. Oh, man, doing it on the drawing is so difficult. Here is the shadow of a cup. That's the shadow of a cup, right? So this is what a 3D object looks like, right? This is what a 3D object looks like, right? It's got a hole in it. Cool. I've been sitting there for a while. It's a little dirty there, right? This is a 3D object, right? This is the shadow of a 3D object, but this is 2D. Now if you look at this thing, 2D, without knowing that that was a cup that has a hole in it, would you know that this has a hole in it? How do you know what a hole is? You live in a 2D plane. What's a hole? Is a hole this? But that's not a sealed hole, right? That was a hole that you could put your finger through it. If you're in a 2D world, how are you going to put your finger through that? You're on a flat surface, right? That's the same way it works for 4D objects. We can see the shadow of a 4D object, but we can't know everything there is about that 4D object unless we still can't, but what we can do is, for example, take this object again and let's draw the shadow this way, right? If you draw the shadow this way, it looks like this. Well, that just looks upside down. What? Here, let me draw it like this. I want to draw it like this. There we go. Let's say we draw it like this. If you draw it like this, you get this. Now it looks like this. If you shine it like this way, well, what is that? If you only had one direction shadow on this three-dimensional object, then you wouldn't know that from the top it looks like that. Now what is that? Unless the bottom was empty as well, if the bottom was empty, it was broken, then it would look like this. Then you'd be going, what? So that's what we can do with 4D dimensional objects, spatial dimensions anyway.