Space and Time

                                                                     Matter

Matter extends, moves and endures. Thus, material existence comprises extension, duration and motion: miles, hours and miles per hour.

Dimensions

The single temporal dimension is often thought to be a fourth spatial dimension. This would reduce motion and duration to extension. However, we are then thought to move along the fourth dimension. This re-introduces motion. Further, motion along the familiar temporal dimension would require endurance in a second temporal dimension. This re-introduces duration. 

We do not move along time at sixty minutes per hour because sixty minutes is an hour. Mere extension and duration are speedless. We cannot accelerate from sixty minutes per hour to sixty minutes per second or from twelve inches per foot to twelve inches per inch. Motion requires two sets of units: sixty minutes (= one hour) per --?

I suggest that: 
 

motion is change of position;
position is spatial relationship;
time is the relationship between states changed from and states changed to;
therefore, time is not a spatial relationship but a relationship between such relationships.

However, time is comparable to a fourth spatial dimension because:

three co-ordinates define a position but a fourth is necessary to define an event;
we can visualize time as a fourth direction at right angles to the three of space;
physicists regard space and time as interchangeable.

 
Even if we do conceive of time as a fourth spatial dimension, we continue to perceive only three-dimensional cross-sections. Accumulating memory generates the illusion that consciousness moves along time from birth towards death. Four dimensionally, a body merely extends from its birth to its death. Consciousness immaterially moving along time would entail not only a second temporal dimension but also a questionable mind-body dualism. Are three-dimensional bodily cross-sections unconscious before the mind reaches them and again afterwards? Or, if bodily behavior is unaffected by the presence or absence of a mind, how do we know that other minds exist? It is simpler to accept that consciousness is material and that spatiotemporal experience is merely four dimensional.

“Time Travel”

Wells’ Time Traveler merely endures longer in an attenuated form. Poul Anderson’s Time Patrollers simply disappear at one set of spatiotemporal co-ordinates and appear at another. Neither moves through time.