There is no fundamental difference between man and the higher mammals in their mental faculties...The difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind.
Charles DarwinThe more we know of the fixed laws of nature the more incredible do miracles become, - that the men at that time were ignorant and credulous to a degree almost incomprehensible by us, - that the Gospels cannot be proved to have been written simultaneously with the events, - that they differ in many important details, far too important as it seemed to me to be admitted as the usual inaccuracies of eye-witnesses; - by such reflections as these... I gradually came to disbelieve in Christianity as a divine revelation.
Charles DarwinI am not very sceptical, — a frame of mind which I believe to be injurious to the progress of science. A good deal of scepticism in a scientific man is advisable to avoid much loss of time, but I have met with not a few men, who, I feel sure, have often thus been deterred from experiment or observations, which would have proved directly or indirectly serviceable .
Charles DarwinThe more I study nature, the more I become impressed with ever-increasing force with the conclusion, that the contrivances and beautiful adaptations slowly acquired through each part occasionally varying in a slight degree but in many ways, with the preservation or natural selection of those variations which are beneficial to the organism under the complex and ever-varying conditions of life, transcend in an incomparable degree the contrivances and adaptations which the most fertile imagination of man could suggest with unlimited time at his disposal.
Charles Darwin