The Grandeur of Evolution in a New Exhibition Called 'Darwin' - New York Times: "In the summer of 1868, Charles Darwin and his family visited the poet Alfred Tennyson and his family on the Isle of Wight. The visit - and the visitor's ideas - troubled Tennyson. 'What I want,' he later told a friend, 'is an assurance of immortality.'
This was an astute remark. Many of Darwin's readers, then and now, have tried to find ways to reconcile a divine creator with the clearly secular implications of Darwin's theory of evolution. As often as not, the effort is less a search for a first cause than a plea for assurances of immortality. Tennyson recognized that Darwin's 'On the Origin of Species,' which was published in 1859, offered no such promises.
What bothered Tennyson wasn't merely the possible loss of eternity. It was also the central observation that underlies Darwin's theory: the fact, first noticed by Malthus, that every species on the planet, including humans, produces far more offspring in each generation than nature can support. Coming as late as we do - nearly a century and a half after Darwin's 'Origin' - we have the luxury of seeing at a glance what Darwin saw: that the pressure of so much excess population is a harsh but efficient test of the value of accidental variations in any species.
We can say, with Thomas Huxley, 'How extremely stupid not to have thought of that!' But, of course, Darwin did not simply think of it. He prepared for years to be ready to think of it when he did. It is one thing to see the logic in evolution, as stated on the page. It is something entirely different to have pieced together such an astonishingly powerful theory - a word that, as scientists use it, means an explanation of the facts as we know them - from the details of nature itself."