I thought today of "gravity" as applying to time.There may be a "free fall" of time, comparable to a free fall of some object towards another object of greater mass. To think of the future as "greater mass" then the past, the present as the least amount of "mass." Thus the future may "pull" time towards itself, in the same way as a large amount of mass pulls objects towards itself. An "infinite past" is not possible- it is finite- but an infinite future is possible; thus, since the future is greater in "mass" than the past, time "moves." But, according to this idea, time should "slow down" gradually, as the past increases in mass, since time would be drawn towards it more and more. (5/15/86)