“Great minds have always seen it. That is why man has survived his journey this long. When we fail to wish any longer to be otherwise than what we are, we will have ceased to evolve. Evolution has to be lived forward. I say this as one who has stood above the bones of much that has vanished, and at midnight has examined his own face.”

“There is nothing more alone in the universe than man. He is alone because he has the intellectual capacity to know that he is separated by a vast gulf of social memory and experiment from the lives of his animal associates.”

“Since the first human eye saw a leaf in Devonian sandstone and a puzzled finger reached to touch it, sadness has lain over the heart of man. By this tenuous thread of living protoplasm, stretching backward into time, we are linked forever to lost beaches whose sands have long since hardened into stone. The stars that caught our blind amphibian stare have shifted far or vanished in their courses, but still that naked, glistening thread winds onward. No one knows the secret of its beginning or its end. Its forms are phantoms. The thread alone is real; the thread is life.”

“We are one of many appearances of the thing called Life; we are not its perfect image, for it has no perfect image except Life, and life is multitudinous and emergent in the stream of time.”

“If 'dead' matter has reared up this curious landscape of fiddling crickets, song sparrows, and wondering men, it must be plain even to the most devoted materialists that the matter of which he speaks contains amazing, if not dreadful, powers, and may not impossibly be, as Thomas Hardy has suggested, 'but one mask of many worn by the Great Face behind.”

“As we passed under a streetlamp I noticed, beside my own bobbing shadow, another great, leaping grotesquerie that had an uncanny suggestion of the frog world about it . . . judging from the shadow, it was soaring higher and more gaily than myself.'Very well,' you will say, 'Why didn’t you turn around. That would be the scientific thing to do.'But let me tell you it is not done ― not on an empty road at midnight.”

“If it should turn out that we have mishandled our own lives as several civilizations before us have done, it seems a pity that we should involve the violet and the tree frog in our departure.”