Did Darwin Banish Teleology from Nature or Not?
I have been reviewing a new collection from Cambridge University Press, Darwin Mythology: Debunking Myths, Correcting Falsehoods. (See my earlier posts here and here.) James G. Lennox opens his essay about Darwin’s views on teleology with Friedrich Engels’s statement in a letter to Karl Marx. Engels exulted that Darwin had demolished teleology. This is a view that is commonplace among many Darwinian biologists, as well as historians. Lennox, however, calls it a myth that Darwin banished teleology from nature.
Lennox defines teleology thus: “A teleological explanation is one in which some property, process or entity is said to exist or be taking place for the sake of a certain result or consequence.” In the course of the essay Lennox points out that when discussing organisms’ adaptations, Darwin often used the language of teleology: “final cause,” “contrivances for this end,” etc.
Lennox also correctly points out that Darwin’s teleology differed from that of Harvard biologist Asa Gray, who argued that teleology implied natural theology. Darwin completely rejected natural theology. Lennox is right that this makes Darwin’s and Gray’s teleology different.
The problem with Lennox’s analysis is twofold: 1) Darwin recognized that his use of teleological language could be problematic; and 2) the kind of teleology that Lennox claims Darwin embraced is trivial compared to the kind of teleology he rejected.
Darwin’s Teleological Language
To be sure, Darwin used teleological language when discussing organisms’ adaptations. Lennox quotes from an 1862 essay, where Darwin wrote that “the final cause of all this mimicry” among butterflies is evading predation. Lennox then states, “It is this valuable consequence of mimicry that explains its selective advantage — that is the end achieved by mimicry.” (p. 191) Thus, Darwin recognized that adaptations had purposes. For instance, the eye has a purpose — it is for seeing.
Sometimes Darwin’s contemporaries criticized him for using teleological language. In 1877 Darwin responded to Alphonse de Candolle’s critique:
There is much justice in your criticisms on my use of the terms object, end, purpose; but those who believe that organs have been gradually modified by natural selection for a special purpose, may I think use the above terms correctly though no conscious being has intervened. I have found much difficulty in my occasional attempts to avoid these terms; but I might perhaps have always spok[en] of a beneficial or serviceable effect.1
Darwin’s claim here that there was some justice in the critique, as well as his confession that he sometimes tried to avoid teleological terms, suggests that Darwin was not entirely comfortable using teleological language. However, he defends the use of teleological language nonetheless, because he believed that adaptations did serve a purpose — helping an organism survive and reproduce in the struggle for existence. In light of this, perhaps Lennox has a point.
The Teleology Darwin Did Banish from Nature
However, Lennox seems to miss the point that, even though Darwin admitted that adaptations served a purpose, he vociferously denied that the evolutionary process was teleological. When Engels and most scholars insist that Darwin banished teleology from nature, they are denying that evolution is a teleological process. They are not denying that specific organs of animals and plants serve specific purposes.
Darwin often stressed that evolution on the whole was non-teleological. In an 1881 letter to William Graham, Darwin stated that his primary disagreement with Graham “is that the existence of so-called natural laws implies purpose. I cannot see this.”2 Both here and in many other writings Darwin explicitly denied the existence of any over-arching purpose for organisms.
In 1861 Darwin wrote to Lyell a letter where he denied that adaptations had originated for a purpose: “No doubt these [i.e., variations] are all caused by some unknown law, but I cannot believe they were ordained for any purpose; & if not so ordained under domesticity, I can see no reason to believe that they were ordained in a state of nature.”3 Since variations are the source of evolutionary change, Darwin was hereby denying that evolution had any goal toward which it was moving.
Darwin often used the term “chance” to describe variations in nature, because he did not believe variations arose for any purpose or toward any goal. This is why Darwinian evolution is a non-teleological process. Thus, despite Lennox’s arguments, it still makes sense to say that Darwin banished teleology from the evolutionary process, even if biological adaptations do serve various purposes.
Notes
Darwin to Alphonse de Candolle, August 3, 1877, Darwin Correspondence Project, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-11092.xml&query=purpose.
Darwin to William Graham, July 3, 1881, Darwin Correspondence Project, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-13230.xml&query=purpose.
Darwin to Charles Lyell, August 13, 1861, Darwin Correspondence Project, https://www.darwinproject.ac.uk/letter/?docId=letters/DCP-LETT-3230.xml&query=purpose.
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