Nothing can better express the feelings of the scientist towards the great unity of the laws of nature than in Immanuel Kant's words: "Two things fill the mind with ever new and increasing awe: the stars above me and the moral law within me."… Would he, who did not yet know of the evolution of the world of organisms, be shocked that we consider the moral law within us not as something given, a priori, but as something which has arisen by natural evolution, just like the laws of the heavens?

Ch. XII : On the Virtue of Scientific Humility - On Aggression (1963)