[Salgat]

Don't conflate physical and logical, in this case we don't care about the physical dimensions, only how the logic is expressed. Even a 2D function can be expressed in N-dimensional parameters, such as

y = a1 * x + a2 * x^2 + a3 * x^3 + a4 * x^4

where you only have one input and one output, but 4 constants that can be adjusted. These 4 constants make up a 4D vector.