...I have always maintained that, excepting fools, men did not differ much in intellect, only in zeal and hard work; and I still think there is an eminently important difference.
Charles DarwinWho when examining in the cabinet of the entomologist the gay and exotic butterflies, and singular cicadas, will associate with these lifeless objects, the ceaseless harsh music of the latter, and the lazy flight of the former - the sure accompaniments of the still, glowing noonday of the tropics.
Charles Darwin... if variations useful to any organic being do occur, assuredly individuals thus characterized will have the best chance of being perserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offsping similarly characterized. This principle of preservation, I have called, for the sake of brevity, Natural Selection.
Charles DarwinUltimately a highly complex sentiment, having its first origin in the social instincts, largely guided by the approbation of our fellow-men, ruled by reason, self-interest, and in later times by deep religious feelings, confirmed by instruction and habit, all combined, constitute our moral sense or conscience.
Charles Darwin