I liked the topic of 4th dimensional space and time being the 4th variable... I stumbled onto this ongoing conversation because I was browsing the internet on this concept. I found many interesting things but the one thing that seems most relevant to this discussion is that we cannot perceive a dimension(please partake of the perceived definition...no sophistry here!) higher than the one we currently reside in. Whatever is the nature of this fifth or fourth dimension is beyond our ability and design to evaluate. So by all means discuss on but it is as an ant in an algebra class he's there but he just don't get it.