If one covers up one eye, then he loses depth perception (two dimensional perspective). When we uncover that eye, we can now see depth (three dimensional perspective). My question is if we had four eyes, would we be able to see from a four dimensional perspective?
Your eyes are really just recording a flat image focused on your retina--it is your brain that extrapolates distance by comparing two images. In a way, you only see in two dimensions.
If you had a third eye, you might have better depth perception (if you had enough brain function to process that much data).
The world we observe with our five senses is three dimensional. Two independent measurements are enough to calculate the three dimensional position of everything, which is what our brain does with the input of two eyes.
More eyes would only over constrain the solution, and might help in low lighting or long distance estimates when the errors are large.