[spintreebob]

This is ridiculous. Three dimensions are based on 90 degree angles. The choice of 90 degrees, rather than 60 degree or any other increment of angularity is strictly arbitrary. It is arbitrary in the same sense that the weight of a kilogram or the length of a foot is arbitrary.

[longshadow]

Three dimensions are based on 90 degree angles. The choice of 90 degrees, rather than 60 degree or any other increment of angularity is strictly arbitrary.

It's not clear what you are trying to say here.

[Doctor Stochastic]

The choice of 90 degrees, rather than 60 degree or any other increment of angularity is strictly arbitrary.

No. Right angles are the only orthogonal system. For example, in two (remember that number) dimensions, the usual 90 degree coordinate system gives two numbers that completely describe a position. A 60 degree system with three lines gives three numbers, but only two are necessary (the third can always be determined from the other two).

A similar result holds for more dimensions. A coordinate system at right angles gives the same number of coordinates as the dimensionality.

Of course, the actual number, 90 is irrelevant; one could have used (with some justification) a number such as 91&5/16 "degrees" for a right angle.