So we have a 0 dimensional point. How does it change its state? It becomes a line and moves from side to side, becoming a 1 dimensional line. Now, how does a 1 dimensional line change its state? It moves north and south to become a 2 dimensional shape: a square, perhaps. How does the square change its state, you ask? It moves up or down, creating a cube (3rd dimensional). Now, how does a 3 dimensional object, such as you or me, change its state? It is affected by time, the 4th dimension. Now, with this, how does the 4th dimension (we'll call it time) change state; how can it be affected? Gravity