I second that.  This perfectly illustrates how I explain it to my friends also, at least when I force them to listen to me talk about N dimensions )  I noticed the X and Y colors in your legend did not match the illustrations, so I uploaded a new version that corrects this (:File:Dimension levels.svg).  I hope that's ok with you.  I don't know what graphics editor you used, but I just fixed it with a text editor to preserve the readability of the file by your original editor.