Not one change of species into another is on record ... we cannot prove that a single species has been changed.

It is a truly wonderful fact - the wonder of which we are apt to overlook from familiarity - that all animals and all plants throughout all time and space should be related to each other in group subordinate to group.

Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult - at least I have found it so - than constantly to bear this conclusion in mind...We behold the face of nature bright with gladness...We do not see, or we forget, that the birds which are idly singing round us mostly live on insects and seeds, and are thus constantly destroying life.

Nothing exists for itself alone, but only in relation to other forms of life

From the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of higher animals, directly follows.

...I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton.— Let each man hope & believe what he can.—

Our faculties are more fitted to recognize the wonderful structure of a beetle than a Universe.