MOUSEBENDER: Good Morning.
WENSLEYDALE: Good morning, sir. Welcome to the National Cheese Emporium.
MOUSEBENDER: Ah, thank you my good man.
WENSLEYDALE: What can I do for you, sir?
MOUSEBENDER: Well, I was, uh, sitting in the public library on Thurmond Street just now, skimming through History of the Inductive Sciences by William Whewell, and I suddenly came over all peckish.
WENSLEYDALE: Peckish, sir?
MOUSEBENDER: (In a broad Yorkshire accent) Eee I were all hungry, like.
WENSLEYDALE: Ah, hungry.
MOUSEBENDER: In a nutshell. And I thought to myself, ‘a little fermented curd will do the trick’. So I curtailed my Whewelling activites, sallied forth, and infiltrated your place of purveyance to negotiate the vending of some cheesy comestibles.
WENSLEYDALE: Come again?
MOUSEBENDER: I want to buy some cheese.
I have for many years been keeping a weather eye out in case a copy of Whewell’s History was up for sale, and last week I found one. It’s the third edition, a reprint of the 1880s, but it’s good enough for me. Now for a copy of the Philosophy of the Inductive Sciences. And some cheese (I wish they’d turn those bouzoukis down a bit).
Why was I Whewelling just now?
Well, Whewell was among other things in Darwin’s circle, and yet he, more than anyone apart from Cuvier, thought that species were immutable. He wrote in the Philosophy: ?species have a real existence in nature, and a transition from one to the other does not exist? (Whewell 1837, v. 3, 626; quoted in Hull 1973b: 68). But in the History, he discusses instead the Natural System as the topic of most interest in Botany. And the Natural System interests me more than most things of that period.
Everyone agreed that Linnaeus’ system was artificial, including Linneans like James Edward Smith and John Lindley. The use of a single character or key to classify species was understood to be a matter of convenience of use. But the real classification would come from the use of many characters, as proposed by Michel Adanson and Antoine Laurent de Jussieu, and this was a live and active debate that continues in various guises until today. A discussion of the Natural System in the work of William Swainson, especially his Preliminary Discourse on the Study of Natural History, in which he praised the Quinarian system of William Macleay as being inductively derived from a natural system. For Whewell, this was where things stood when he wrote, in the 1840s.
Now from Whewell and to a lesser extent Mill’s discussion of natural kinds, some have drawn the conclusion that the naturalists themselves saw taxa, particularly species, as classes, about which Whewell said in reply to the Origin that they were fixed and could not therefore evolve. The centrality of this view amongst naturalists is not borne out by my reading. Many if not most naturalists in the early years of the nineteenth century allowed that species were not fixed by some definitional essence. It looks to me as if the philosophers are the source of this story, and that they were in general not influential upon the naturalists in that regard, as Whewell was not upon his one-time student Darwin.
But Whewell’s interest in the Natural System debate in the History is most revealing. If taxa were in fact natural kinds, he did not expect that they would have a simple set of properties that defined them, but rather an overall set of properties, none of which was sufficient on its own, just as Jussieu said. Taxonomy, like the rest of science, was to be consilient – taking many independent lines of evidence concurrently.
Why is this relevant today? Well it appears that modern taxonomy applies just this methodus in cladistic taxonomy. Many characters are coded, not merely a few genetic markers or some overall impression of similarity, and the result is a hierarchical classification that is as close to being natural as it can be, although unlike the Jussieuian system, some characters must be eliminated first as uninformative (that is, as convergences). So I am keen to find out more about how that debate developed. Even Darwin was influenced by it in no small degree.
Enough cheese, or the lack of it. Back to my Whewelling…