If an architect were to rear a noble and commodious edifice, without the use of cut stone, by selecting from the fragments at the base of a precipice, wedge-formed stones for his arches, elongated stones for his lintels, and flat stones for his roof, we should admire his skill and regard him as the paramount power. Now, the fragments of stone, though indispensable to the architect, bear to the edifice built by him the same relation which the fluctuating variations of organic beings bear to the varied and admirable structures ultimately acquired by their modified descendants.
Some authors have declared that natural selection explains nothing, unless the precise cause of each slight individual difference be made clear. If it were explained to a savage utterly ignorant of the art of building, how the edifice had been raised stone upon stone … it would be unreasonable if he declared that nothing had been made clear to him, because the precise cause of the shape of each fragment could not be told. But this is a nearly parallel case with the objection that selection explains nothing, because we know not the cause of each individual difference in the structure of each being." Charles Darwin (1868) The Variation of Plants and Animals under Domestication, [page 426] [HT David Haig.]
Earlier in the week (recall), I noted that in Origin of Species (right at the start, in fact) one of Darwin's argumentative strategies, relying on was indebted to Hume and Adam Smith, is to rely on the ignorance of savages for heuristic purposes. This strategy entails that i) one is not allowed to attribute knowledge of (to use eighteenth century terminology) remote consequences to the intentions of ancient savages and that (ii) even in domestication and artificial selection there are unintended consequences. But this is not the only methodological use of the ignorant savage. (Again, I ignore the racial issues lurking in the corner here.) He famously closes the Origin, with a related use: "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!" So, the lack of knowledge of savages frames Origin.
The origin and function of this savage-ship trope in ideas on the division of labor and the slow development of technology (illustrated by ships) in Mandeville and Hume has been articulated by Stephen Alter in a very nice essay (HT Catherine Kemp an her important essay). However in Mandeville and Hume the ignorant savage is absent in this particular ship trope!
As Alter notes, a very similar trope (about savages) ends Descent of Man (1871) "He who is not content to look, like a savage, at the phenomena of nature as disconnected, cannot any longer believe that man is the work of a separate act of creation." The target is the theory of separate creation. Such an idea (of special creation) is made possible or conditioned -- historically one may say -- by the inability to see nature as connected (and presumably) law-governed. Here Darwin also echoes Hume (The Natural History of Religion) and Smith (The History of Astronomy and the History of Ancient Physics), where science is first made possible, in the context of the political escape of the state state of nature, by the achievement of treating nature as connected and regular (see my book for details).
So, much for set-up.
At the top of this post, I quoted the closing lines of Variation. The underlying conceit is that natural selection can explain the machinery behind the origin and variety of domestic and non-domesticated species. As Darwin acknowledges it can't explain everything, and the point of the savage being explained the role of an architect and his tools in a a building, is that it is not an objection to Darwin's theory that it can't do so (in particular explain the reason why in nature small differences -- the raw materials for selection -- spontaneously seem occur). Let's grant Darwin his claims. Darwin's use of an architect example is not innocent, of course, because God is often likened to a divine architect (the house/divine architect analogy is a prominent target in Hume's Dialogues).
One may well wonder why our distance from the savage's understanding of the hidden machinery of nature is such a recurring trope in Darwin. While I don't deny the autobiographical significance of his encounter with 'non-civilized' peoples in his travels, and the more general sense of cultural superiority of Victorian England, I think there is also an explanation rooted in the history of ideas and what I have been calling the Posidonian argument. Recall Cicero's argument:
But if all the parts of the universe have been so ordered that they could not have been better adapted for use, or more beautiful as regards appearance, let us see whether they are the work of chance, or whether their arrangement is one in which they could not possibly have been combined except by the guidance of consciousness and the divine providence. If, then, the things achieved by nature are more excellent than those achieved by art, and if art produces nothing without making use of intelligence, nature also ought not to be considered destitute of intelligence. If at the sight of a statue or painted picture you know that art has been employed, and from the distant view of the course of a ship feel sure that it is made to move by art and intelligence, and if you understand on looking at a horologe, whether one marked out with lines, or working by means of water, that the hours are indicated by art and not by chance, with what possible consistency can you suppose that the universe which contains these same products of art, and their constructors, and all things, is destitute of forethought and intelligence? Why, if any one were to carry into Scythia or Britain the globe which our friend Posidonius has lately constructed, each one of the revolutions of which brings about the same movement in the sun and moon and five wandering stars as is brought about each day and night in the heavens, no one in those barbarous countries would doubt that that globe was the work of intelligence.--Cicero, On the Nature of the Gods.
In Cicero's argument, when confronted by an intricate, successful representation of the movements of nature, a savage/barbarian will immediate grant that the representation is the product of artificial design. If one then grants the premise that artifice "produces nothing without making use of intelligence, nature also ought not to be considered destitute of intelligence" in virtue of the fact that nature is superior (in some sense) to artifice, some cleaned up version of the argument goes through (see this reconstruction by Hunter). That nature is superior to artifice, I dub nature's superiority premise. As regular readers know, I have been interested in a particular version(s) of this so-called Posidonian argument, revived and articulated in the early modern period (see here on Dennett and Descartes, here on Boyle's plagiarism, here on Locke/Newton, here on Voltaire, and Voltaire and Spinoza, etc.). My particular interest in the argument is made clear by the following (rational) reconstruction:
(I) A necessary condition of the possibility of (an (intended)) successful scientific representation or concrete model of (a region of) nature is that (a region of) nature is orderly;
(II) (A region of) Nature’s hidden order could not be the product of chance [as suggested by Epicureanism] or necessity [as suggested by Spinozism], but only by an Ordering God/Very powerful/infinite mind;
(III) [It’s possible that] Science produces successful representations and successful concrete models of (a region of) nature.
(IV) ∴ There is a God (of order).
In my reconstruction, Cicero''s nature's superiority premise is suppressed, but it lurks behinds (I) and (III). The savage's assent that surely the machine is (intelligently) man-made is suppressed in (III). [I leave it as an exercise to the reader to reinstate them into a longer rational reconstruction.] Even so, the savage/barbarian gazing at the machine shows up throughout the sources.
Let me, in closing, return to Darwin. I think the framing of his arguments by way of a savage is explained by the known pull of the Posidonian argument on his readers (and perhaps himself). It should come as no surprise, then, that Darwin explicitly endorses a version of nature's superiority premise in Origin: "But Natural Selection, as we shall hereafter see, is a power incessantly ready for action, and is as immeasurably superior to man's feeble efforts, as the works of Nature are to those of Art."--(Chapter 3.) The echoes to Cicero's Posidonian argument are unmistakably. (As noted, Cicero's argument known in various guises throughout the eighteenth century. (In my view Paley does not present the strongest version of it, but that's for another time.) Darwin's innovation is that rather than speaking of nature as such, he speaks of natural selection. And the effect of that substitution is to make transparent that premise (II) misses at least alternative. So, it needs needs to be rewritten.
(II*) (A region of) Nature’s hidden order could not be the product of mere chance [as suggested by Epicureanism]* or mere necessity [as suggested by Spinozism],+ but only by an Ordering God/Very powerful/infinite mind or Natural Selection.
The relationship between (a) natural selection and an ordering god and between (b) natural selection as an alternative to Epicureanism and/or Spinozism is not transparent. The significance of this point is not, primarily, that the conclusion of the Posidonian argument is now undermined (after all a Deist will be untroubled by the existence of natural selection), but rather that the functionality of the Posidonian argument as such is destabilized. It's fruitfulness as a thinking device comes to an end with Darwin.