"We know, for example, that there has existed a more or less complete chain of beings from monad to man, that the one-toed horse had a four-toed ancestor, that man has descended from an unknown ape-like form somewhere in the Tertiary." "We _know_"--that is exactly the opposite of the truth. We _know_ a thing when it is susceptible of proof according to the rigid rules of formal logic; when, to doubt it, would be to give rise to a suspicion as to our sanity; then we _know_ a thing, but not until then. Now, as to the sentence quoted, we may allow the first part to pass unchallenged with some possible demur at the use of the word "chain." The second so-called piece of knowledge was doubted by no less an authority than the late Adam Sedgwick. The third assertion plainly and distinctly is not the case; for Science _knows_ nothing whatsoever about the origin of man's body. In 1901 Branco, a distinguished palaeontologist, with no Theistic leanings as far as we know, told the world that man appears on our planet as "a genuine _homo novus_," and that palaeontology "knows no ancestors of man." Nor has any discovery since that date necessitated the modification of that opinion. What the writer means by saying "_We_ know" is "_I_ am convinced"; but, with the deepest respect for his undoubted position, the two things are not quite identical. "Biology, like theology, has its dogmas. Leaders have their disciples and blind followers." Wise words! They are those of the author with whom we are dealing. To say "we know" when really we only surmise is a misuse of language, just as it is also a misuse to ask the question "Does nature make a departure from its previously ordered procedure and substitute chance for law?" since the ordinary reader is all too apt to forget that "Nature" is a mere abstraction, and that to speak of Nature doing such or such a thing helps us in no way along the road towards an explanation of things.