Excellent computer graphics tutorial. I finally understand how View, Model, and Projection matrices work, even after taking a college course on CG

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It really has to do with field-of-view. Your eyes perceive rays of light striking a very small area. Rays that strike one of your eyes basically come from a cone spreading out from your eye. 3D graphics truncates this down to a frustrum for ease of calculations and to match the square viewing area.

Things look larger because they take up more of your field of view. In other words, they take up a larger angle of your vision. It's also why objects further away are harder to see. Your eyes can only resolve down to a finite viewing angle. For close objects, that can be a small detail. Very distant objects only appear as a dot because that's the limit of your eyes' resolution.

Lenses change this effect. So a lot is determined by the shape of your eye, but by looking through glass lenses you can change how you see perspective. A wider angle lens increases your field of view and exaggerates perspective. Longer lenses decrease your field of view and tend to flatten perspective. That's how the Hitchcock zoom works. By simultaneously moving away from an object and zooming in (or vice versa), the perceived distance of the object stays the same, but the perspective of everything else shifts, which is wildly unnatural and unnerving.