Are There Coordinates for the Fourth Dimension?

The interest in the fourth dimension is ever increasing. We all keep asking: Can there really exist a fourth dimension? In what direction should we look to find it? Why there are so many interpretations of it?

Is the spiritual fourth dimension the same as the physicists' interpretation? What is doing the mathematics about it?

Image of a simple four-legged table.
The legs of a table do not have
any naming order. 
Well, to begin with, we all agree that WE ALL LIVE in three dimensions. That's a good start, but we do not all agree which one is THE FIRST DIMENSION. We don't know which dimension is the SECOND DIMENSION; so, how can we all agree which dimension should be the FOURTH DIMENSION?

To study the fourth dimension from the geometrical or algebraic standpoint of view we should associate dimensions with coordinates in a spatial hyperspace. This approach leads us to ask: Are there coordinates for the fourth dimension?

In the article, The Coordinates of the Fourth Dimension, I use the figure of a little dining table to ask which one of the four legs of the table we should say is THE FIRST LEG, which one of the four legs is the FOURTH LEG.

Take the challenge, read the article,  and be the first one to answer the question and fill in the blanks: In any table, the first leg is determined by ...!