It is perfectly possible that in the general spectrum of Life the line ending in Man was originally no more than one psychic radiation among countless others. But it happened, for some reason of hazard, position or structure, that this sole ray (this is an experiential fact) among the millions contrived to pass the critical barrier separating the Unreflective from the Reflective—that is to say, to enter the sphere of intelligence, foresight and freedom of action. Because it did so (and although in a sense, I must repeat, this ray was only one attempt among many) the whole essential stream of terrestrial biological evolution is now flowing through the breach which has been made. The cosmic tide may at one time have seemed to be immobilized, lost in the vast reservoir of living forms; but through the ages the level of consciousness was steadily rising behind the barrier, intil finally, by means of the human brain (the most ‘centro-complex’ organism yet achieved to our knowledge in the universe) there has occurred, at a first ending of time, the breaking of the dykes, followed by what is now in progress, the flooding of Thought over the entire surface of the biosphere.
Thus regarded, everything in history of the world takes shape, and what is better, everything goes on.
from an Essay, “Turmoil or Genesis?” by