I have long observed that much severity leads the reader to take the side of the attacked person. . . . As you will surely play a great part in science, let me as an older man earnestly beg you to reflect on what I have ventured to say. I know that it is easy to preach & if I had the power of writing with severity I dare say I shd triumph in turning poor devils inside out & exposing all their imbecility. Nevertheless I am convinced that this power does no good, only causes pain. I may add that as we daily see men arriving at opposite conclusions from the same premises it seems to me doubtful policy to speak too positively on any complex subject however much a man may feel convinced of the truth of his own conclusions.
Charles Darwin to Ernst Haeckel, 12 April  See the letter
Much of the Victorian debate over science and religion took place among members of a community that was broadly tolerant and even open to religious change. What emerges from the correspondence is a much richer picture of the period than is presented in the secondary literature, or in popular portrayals of the debates over evolutionary theory, which emphasise conflict and polarisation. The nineteenth century also had its polemicists (Huxley and Wilberforce were among the most accomplished): those who sought to turn Darwinism to political advantage, to create polarities between different groups, and to establish clear-cut distinctions and choices (good or evil, ignorance or knowledge, religion or science). But if one looks beyond these often highly familiar cases and frequently cited sources, one finds a broad spectrum of opinion, a spirit of genuine enquiry, and a sense of openness, tolerance, and humility in this earlier chapter of the science and religion debate that can usefully be brought to bear on present understandings. Darwin himself, though a spirited debater with some of his correspondents, was also immensely humble both with respect to the limits of his own knowledge, and the achievements and potential of science. One of the most important lessons to be learned from history is the lesson of humility.