Je cherche à comprendre.

The scientific attitude implies the postulate of objectivity-that is to say, the fundamental postulate that there is no plan; that there is no intention in the universe.

The whole concert of animate nature arose entirely from annoying noises.

Even today a good many distinguished minds seem unable to accept or even to understand that from a source of noise natural selection alone and unaided could have drawn all the music of the biosphere. In effect natural selection operates upon the products of chance and can feed nowhere else; but it operates in a domain of very demanding conditions, and from this domain chance is barred. It is not to chance but to these conditions that eveloution owes its generally progressive cource, its successive conquests, and the impresssion it gives of a smooth and steady unfolding.

...the scientific attitude implies what I call the postulate of objectivity-that is to say, the fundamental postulate that there is no plan, that there is no intention in the universe. Now, this is basically incompatible with virtually all the religious or metaphysical systems whatever, all of which try to show that there is some sort of harmony between man and the universe and that man is a product-predictable if not indispensable-of the evolution of the universe.

Every living being is also a fossil. Within it, all the way down to the microscopic structure of its proteins, it bears the traces if not the stigmata of its ancestry.

The fundamental biological variant is DNA. That is why Mendel's definition of the gene as the unvarying bearer of hereditary traits, its chemical identification by Avery (confirmed by Hershey), and the elucidation by Watson and Crick of the structural basis of its replicative invariance, are without any doubt the most important discoveries ever made in biology. To this must be added the theory of natural selection, whose certainty and full significance were established only by those later theories.