A few--okay, many--further thoughts on the last two chapters. May try to post with further thoughts on the Origin as a whole at some point, but I'll probably wait until around the time of the last class (but don't let that stop you from posting your own lookback on the whole "long argument").
1. The idea that classification was based on evolutionary principles without actually realizing it has intriguing implications. For instance, does that comprise evidence for those evolutionary principles? I'm reminded of the argument (discussed in one of Gould's essays, I believe) that biological species, as classified by taxonomists, are "real" entities because hunter-gatherer tribes classify organisms in the same way (i.e. they recognize each biological species as a distinct kind of organism and give it its own name). Or maybe that thought doesn't stand up to the scrutiny you all will surely apply to it next week as part of your discussion of Darwin's species concept. ;-)
2. I love the final passages of the Origin (from the bottom of p. 480 on) more than I can say. It's so satisfying to see Darwin rising to the occasion and finishing with a flourish. All the caveats and doubts drop away as he drives home the argument and its enormous implications. And it's beautifully written, it just sweeps you along. My highlights (warning: long list!):
(a) p. 481: "But the chief cause of our natural unwillingness to admit that one species has given birth to other and distinct species, is that we are always slow in admitting any great change of which we do not see the intermediate steps." Yup (although I don't know that this is true of today's evangelical creationists; their unwillingness has other sources).
(b) p. 481: "Although I am fully convinced of the truth of the views given in this volume...I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite mine. It is so easy to hide our ignorance under such expressions as the 'plan of creation,' 'unity of design,' &c., and to think that we give explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject my theory...but I look with confidence to the future, to young and rising naturalists, who will be able to view both sides of the questions with impartiality." Oh no he didn't! This is stunningly direct. He might as well have written "The close-minded old farts who dominate the field are so blind they can't even see that their so-called 'explanations' are empty. I can't hope to change their minds because science advances one death at a time. But history will show that I'm right and they're wrong." I'm sure this would read as arrogant--except that history did indeed prove Darwin right. As Reggie Jackson once said in a different context, "It ain't braggin' if you can do it."
(c) p. 483, the rhetorical attack on the emptiness of special creationist 'explanations': "These authors seem no more startled at a miraculous act of creation than at an ordinary birth. But do they really believe that at innumerable periods in the earth's history certain elemental atoms have been commanded suddenly to flash into living tissues? Do they believe that at each supposed act of creation one individual or many were produced?...and in the case of mammals, were they created bearing the false marks of nourishment from the mother's womb? Although naturalists very properly demand a full explanation of every difficulty from those who believe in the mutability of species, on their own side they ignore the whole subject of the first appearance of species in what they consider reverent silence." Wow. One gets the sense here that deep down Darwin is quite frustrated and even angry with special creationism. I imagine that, if one is an open-minded fact hound like Darwin, if one is absolutely determined to get things right, then one is likely to be very impatient with those who aren't equally open-minded and determined. And one is likely to be especially impatient with those who aren't even sufficiently open-minded to recognize and engage with questions so big as to demand an answer. Clearly Darwin took seriously the mottoes from Whewell and Bacon with which he chose to preface his book.
(d) p. 484: "[P]robably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed." Talk about following the evidence wherever it leads. At the time, it would've seemed like a very good question to ask just how far Darwin's argument goes. One might well have wondered, why couldn't there have been several or even quite numerous events of special creation (say, one per family), with evolution by natural selection merely driving subsequent within-family diversification? But there's no evidence for this, and so Darwin calls it like he sees it: the Tree of Life has one root. When I started reading the Origin, I was most impressed with Darwin's insight regarding the mechanism of adaptive evolution. But this passage really convinces me that his insight regarding the fact of evolution was equally impressive. Not only is there an evolutionary Tree of Life--it has one root! No pun intended here but--my God! I wish I could forget what I know about evolution and read that as it would've read to a Victorian. Because in all likelihood I'll never have the chance to be told something that astonishing about the world--something that runs so counter to my whole picture of how the world works. I'll never get to have my world turned upside down. Then again, if I was told something that would turn my world upside down, I'd probably dismiss it as wrong, if not crazy. I'd have to hope I had the insight of Thomas Henry Huxley, who wrote upon reading the Origin, "How extremely stupid not to have thought of that."
(e) p. 485: "When we no longer look at an organic being as a savage looks at a ship, as at something wholly beyond his comprehension; when we regard every production of nature as one which has had a history; when we contemplate every complex structure and instinct as the summing up of many contrivances, each useful to the possessor, nearly in the same way as when we look at any great mechanical invention as the summing up of the labour, the experience, the reason, and even the blunders of numerous workmen; when we thus view each organic being, how far more interesting, I speak from experience, will the study of natural history become!" Great analogy. And a great summary of the modern scientific mind. To a scientist, things become more wonderful, not less, the more we learn about them.
(f) p. 488: "Light will be thrown on the origin of man and his history." Perhaps the most famous understatement of all time.
(g) p. 489. God love him, Darwin saves the best for last. Maybe for some people, the beauty of some famous passages of literature is dulled by familiarity. But for me, the final paragraph of the Origin, with which I was familiar before the term started, will never get old. Indeed, I used to regard it as merely a nice passage. But having read the book I now see it as it was intended, as a summary of everything that came before. And so now this passage impresses and thrills me more than I can say. I am not a religious person, and like many such people if you asked me, "So what do you believe in?" I would struggle to articulate a satisfying answer, by which I mean a spiritually (rather than intellectually) satisfying answer. But although I would struggle to speak for myself, I'm happy to let this passage speak for me. This is the best thing I've ever read:
It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing in the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us. These laws, taken in the largest sense, being Growth with Reproduction; Inheritance which is almost implied by reproduction; Variability from the direct and indirect action of the external conditions of life, and from use and disuse; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less-improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling according to the fixed law of gravity, from so simple a beginning endless forms most beautiful have been, and are being, evolved.