Given our 3-dimensional perspective of the universe, we have created the relative spacial directions of left, right, up, down, forward, and backward, which more or less correspond to the mathematical measurements of length, height, and width. Now, there is a measurement (of which I'm vaguely aware of) coined by Henry More called spissitude, for the hypothetical travels along a 4th spacial dimension. To phrase my question as an analogy, height is to up and down as spissitude is to what?
Thanks!
I think the most intuitive answer is that spissitude is to forward and backward as height is to up and down. You could imagine a particle moving in four dimensions, and easily communicate that it is "moving back and forth in the 4th spacial dimension".