The doctrine of organic evolution, which forever established the common genesis of all animals, sealed the doom of anthropocentricism. Whatever the inhabitants of this world were or were thought to be before the publication of ‘The Origin of Species,’ they never could be anything since then but a _family_. The doctrine of evolution is probably the most important revelation that has come to the world since the illuminations of Galileo and Copernicus. The authors of the Copernican theory enlarged and corrected human understanding by disclosing to man the comparative littleness of his world—by discovering that the earth, which had up to that time been supposed to be the centre and capital of cosmos, is in reality a satellite of the sun. This heliocentric discovery was hard on human conceit, for it was the first broad hint man had thus far received of his true dimensions. The doctrine of evolution has had, and is having, and is destined to continue to have, a similarly correcting effect on the naturally narrow conceptions of men. It tends to fry the conceit out of us. It has been impossible since Darwin for any sane and honest man to go around bragging about having been ‘made in the image of his maker,’ or to successfully lay claim to a more honourable origin than the rest of the creatures of the earth. And if men had accepted the logical consequences of Darwin’s teachings, the world would not to-day—a half-century after his revelation—be filled with practices which find their only support and justification in out-of-date traditions. But logical consequences, as Huxley observes, are the official scarecrows of that large and prolific class of defectives usually known as fools. The doctrine of evolution is accepted in one form or another by practically all who think. It is taught even in school primers. But while the _biology_ of evolution is scarcely any longer questioned, the _psychology_ and _ethics_ of the Darwinian revelation, though following from the same premises, and almost as inevitably, are yet to be generally realised. Darwin’s revelation, like every other revelation that has come to the world, is perceived most tardily by those working in departments where the phenomena are the most intangible and complicated.