Last updated on 18 Sep 2017
Biological topics are used widely in philosophy to illustrate arcane and recondite philosophical topics,and one of the most widely used, and most abused, are species as examples of natural kinds. Kangaroos, swans, tigers, lions, cats, and of course humans are all brought in to assist our intuitions. As Umberto Eco wrote once,
The history of research into the philosophy of language is full of men (who are rational and mortal animals), bachelors (who are unmarried adult males), and tigers (though it is not clear whether we should define them as feline animals or big cats with a yellow coat and black stripes). [1999: 9]
Why this is, is obvious. We need to understand abstract concepts of science and philosophy in terms that we are easily disposed to appreciate. Humans are classifiers of their world and the things they most easily classify are other (large, moving) living things. It’s our Umwelt. But this leads to all kinds of problems. There is a thing known as folk taxonomy, in which the default cultural assumptions of a society are imposed upon the living world. One of the basic tasks of a science is to overcome the folk taxonomy and find out, or classify the world, so that the local biases and simple misunderstandings of the tribe are eliminated and the classifications denote actual things.
Still, philosophers use species as natural kind terms, when every biologist knows this fails in most if not all cases. It might not even be malign: if what you are doing is discussing the meaning of words, then English (or German, etc.) words that denote kinds of animals and plants can stand in for natural kind terms, so long as nobody is thereby misled into thinking that because there is a word, there is out there in the world a kind that answers directly to it. I wish I could say this was a truism all philosophers understood.
Actual species are messy items in the world. Philosophers of biology (that subset of philosophers who attend closely to the uses and ideas of biological sciences rather than resting content with “what everybody knows” about biology) argue at length about essentialism, in which species and other kind terms in biology are supposed to share properties that are uniquely theirs, versus individualism, a somewhat complex suite of ideas that rest upon the assumption that species and other groups in biology are historical objects that have their properties contingently. Philosophers of language try to resurrect essentialism, or treat species as the very exemplar of a natural kind, but generally this fails. The lessons are, slowly, being learned.
But there is a higher level error that can be made, and it has just been made by Christy Mag Uidhir and P.D. Magnus in a paper forthcoming in Metaphilosophy. The paper is titled “Art Concept Pluralism”, and is an argument that the very concept of art is pluralistic. An analogy is drawn, not with a species, but with the concept of species itself, a subject about which I have a few ideas of my own. Now Magnus himself drew attention to a mistake he made by a cursory reading of the literature. He “used” a “concept” of species that he called “the phenetic concept”, and says:
The PHENETIC SPECIES concept (also called morphological or typological) divides species based on organisms’ exhibited characteristics.
This is wrong. It is, indeed, as wrong as a wrong thing can be wrong. I won’t go into the details, but it is not all, or even most, of Mag Uidhir and Magnus’ doing. Types and morphology are distinct, and phenetic means something else, although not quite what Magnus says in the blog entry. He writes
… biologists and philosophers of biology use the word [phenetic] more narrowly to distinguish a specific movement: people who self-identified as employing a phenetic approach and who distinguished species just by doing statistical analyses of observable features
Umm, no. “Phenetic” means the use of multivariate character components in an analysis using clustering algorithms. Not just any statistical analysis will do, and a few characters would not make an analysis phenetic. More widely, a phenetic approach treats not species, but “Operational Taxonomic Units” which are rank-free objects right up to and including entire phyla, or down to single individuals. There is no “phenetic species concept”; that’s the entire point. And phenetic is not something one defines in relation to other approaches such as “pattern cladist” or “biological … ecological … and evolutionary approaches”, either. It is a well defined and coherent approach. If none of those other approaches existed, it would remain well defined.
I’m being picky, I know. The distinction between “character-based” and “process-based” that he makes has some purchase, although I would suggest that it is the distinction between empirical and theoretical classifications. But despite his honesty and self-correction, there is an interesting, and crucial, point in their paper that he has not corrected.
First, let me note that he is using a folk taxonomy of scientific concepts. Scientists do use concepts and words in ways that are relatively reflexive, but that doesn’t mean we should take them at their word. Like any subject of investigation, they are as likely to employ culturally biased and sociologically determined meanings as anyone else. They are a tribe. As philosophers we have to look at them closely and determine if they are clear on their ideas or not. The essentialist story I have so often railed against is just such a social construction. But that is not Magnus’ problem, that is mine.
However, he invents a concept and then crucially uses it in the argument. Here is the way he does so with Mag Uidhir. ART (concepts are capitalised) is like SPECIES, and what is true of SPECIES may be, mutatis mutandis, true of ART. We know species concepts are pluralistic, and so too may concepts of art be. Multiple concepts of SPECIES are used by biologists profitably, so we can presume this for ART. While one might dispute untrammelled pluralism works in biology, either to delimn the natural world or to aid communication, thus far an argument has been made. Then this:
Some of the concepts involve an arbitrary fineness of grain. Using the PHENETIC SPECIES concept, biologists may make species larger or smaller depending on the refinement of their observations and their need to distinguish populations from subpopulations. The PHYLOGENETIC SPECIES concept is similarly plastic. For a monist who thinks that there is a single correct partition of species, this open parameter in a SPECIES concept is a terrible embarrassment. Provided specific biological projects sufficiently constrain the scope of a SPECIES concept, the pluralist may simply accept this result.
What he seems to be saying is that we can enlarge or reduce the scope of a species kind term arbitrarily. But the arbitrariness in phenetics is the threshold at which we include or not organisms in the OTU. It depends, rather centrally, on what we know about the organisms. For bacterial species, we may use a 70%, or a 95% or even a 99% threshold of clustering and similarity. We cannot just arbitrarily say that we will pick one of these in order to redescribe or reclassify bacteria. You do that based on what works at identifying relevant strains or ecotypes and so forth. In fact bacteriologists use a “polyphasic” approach, utilising multiple lines of evidence (genetic, molecular, phenotypic, ecological, cf. Colwell 1970 and Vandamme, et al. 1996). What is arbitrary is what the natural world makes work, not the choices of the taxonomists. Iterative refinement of the thresholds depends on what nature does.
But is there an “open parameter” here anyway? Well not if you think that we can identify species in the absence of prior theoretical commitments, as I do. In other words, we may have no rank for species, as Ereshefsky (1999, 2000) argued, but that hardly licenses the view that species is entirely arbitrary, to be identified as it suits the taxonomist. We named species in the 16th century, before any definitions or theory existed, that we still think are species. That needs explanation. My answer is that we observe species, often. Species are phenomena.
The same point can be made for the so-called “phylogenetic species concept” cluster of ideas. If there are unique traits that all and only members of a species have, which we have identified, then perhaps the PSC will enable us to identify species. But most species have structure well below the species level, such as haplotype groups. We do not identify them as species (although taxonomic inflation is a serious problem in conservation, mostly to do with the over-reliance upon molecular genetic criteria). But pretty well any specialist in, say, fishes or beetles or even eucalypts will be able to say where the species are, nearly all the time.
How does this affect the argument given? ART is a human concept, based upon what humans do and think. SPECIES is not. If there are many kinds of SPECIES, it may be because the world is complex. I have previously argued that the modality of a species is an evolved property, like a trait. Such properties are historically contingent. One cannot be an unrestrained pluralist. Can one be unrestrained about ART? I cannot say. It seems to me that what counts as art has more to do with social structures, economics and functional roles than it does any shared meaning, but that is perhaps my cynicism in play. In any case, the parallel with SPECIES is fraught with problems.
Colwell, Rita R. 1970. Polyphasic taxonomy of bacteria. Culture collections of microorganisms:421–436.
Eco, Umberto. 1999. Kant and the Platypus: Essays on language and cognition. London: Vintage/Random House.
Ereshefsky, Marc. 1999. Species and the Linnean hierarchy. In Species, New interdisciplinary essays, edited by R. A. Wilson. Cambridge, MA: Bradford/MIT Press:285-305.
Ereshefsky, Marc. 2000. The poverty of Linnaean hierarchy: a philosophical study of biological taxonomy. Cambridge, UK; New York: Cambridge University Press.
Vandamme, P., B. Pot, M. Gillis, P. de Vos, K. Kersters, and J. Swings. 1996. Polyphasic taxonomy, a consensus approach to bacterial systematics. Microbiol Rev. 60 (2):407–438.