Evolution: The Modern Synthesis.

Today the god hypothesis has ceased to be scientifically tenable, has lost its explanatory value and is becoming an intellectual and moral burden to our thought. It no longer convinces or comforts, and its abandonment often brings a deep sense of relief.

...any belief in supernatural creators, rulers, or influencers of natural or human process introduces an irreparable split into the universe, and prevents us from grasping its real unity. Any belief in Absolutes, whether the absolute validity of moral commandments, of authority of revelation, of inner certitudes, or of divine inspiration, erects a formidable barrier against progress and the responsibility of improvement, moral, rational, and religious.

To speculate without facts is to attempt to enter a house of which one has not the key, by wandering aimlessly round and round, searching the walls and now and then peeping through the windows. Facts are the key.

Many people assert that this abandonment of the god hypothesis means the abandonment of all religion and all moral sanctions. This is simply not true. But it does mean, once our relief at jettisoning an outdated piece of ideological furniture is over, that we must construct something to take its place.

By speech first, but far more by writing, man has been able to put something of himself beyond death. In tradition and in books an integral part of the individual persists, for it can influence the minds and actions of other people in different places and at different times: a row of black marks on a page can move a man to tears, though the bones of him that wrote it are long ago crumbled to dust.

This earth is one of the rare spots in the cosmos where mind has flowered. Man is a product of nearly three billion years of evolution, in whose person the evolutionary process has at last become conscious of itself and its possibilities. Whether he likes it or not, he is responsible for the whole further evolution of our planet.