The evolution of life is shown as a continuation of the evolution of chemical complexity. The pattern of evolutionary development is the orderly "complexification" of some aggregates of material and their subsequent integration to form organisms on a higher level of orderly complexity with unpredictable emergent qualities. The evolution of humanity is shown as consistent with this pattern & the human species is shown to be currently undergoing a radical transformation into a "Societal Organism".

The author in the final chapter speculates by extrapolation about possibilities in the human future.

The author who is still living has recently published an essay bringing the antiquated biology of the book more up to date and reflecting on his current views & his life. The essay is available on the net if you search for "Fred Kohler, Reflections".