It would be a delicate question to decide what is the minimum period of time which must be assured to man for his future development, in order that Progress should possess value and appeal to the emotions.
The recorded history of civilisation covers 6000 years or so, and if we take this as a measure of our conceptions of time-distances, we might assume that if we were sure of a period ten times as long ahead of us the idea of Progress would not lose its power of appeal.

Sixty thousand years of HISTORICAL time, when we survey the changes which have come to pass in six thousand, opens to the imagination a range vast enough to seem almost endless.
This psychological question, however, need not be decided.

For science assures us that the stability of the present conditions of the solar system is certified for many myriads of years to come.

Whatever gradual modifications of climate there may be, the planet will not cease to support life for a period which transcends and flouts all efforts of imagination.

In short, the POSSIBILITY of Progress is guaranteed by the high probability, based on astro-physical science, of an immense time to progress in.
It may surprise many to be told that the notion of Progress, which now seems so easy to apprehend, is of comparatively recent origin.