Vale Michael Ghiselin

Michael Ghiselin, who was the originator of (the modern) view that species are individuals, died on 14 June 2024. He was a very generous person with his time for antipodean philosophers. With his passing, the authors of the SAI thesis, as it is called, are both gone: he and his close friend David Hull, who passed in 2010.

Ghiselin was a specialist in sea slugs, but he was much more widely read than this topic, and his argument that species are not classes but individuals basically carried the day in philosophy of biology up until quite recently. I still agree that species are individuals, although I would prefer to make a more explicit distinction between general and particular. Metaphysically, I think species are historical particulars.

Ghiselin’s book The Metaphysics of Species (1997) muddled a few philosophical topics though, in my opinion. He seemed to think that individuals/particulars had to be cohesive systems, functionally united. They do not, speaking from metaphysics. For most of western philosophy after Aristotle, particulars were thought to be propositions or predicables. Moreover, something can be a historical particular without cohesion. An example is a constellation of stars. It is neither cohesive, nor is it enduring. Instead it is just a passing pattern, a phenomenon.

As a metaphysical claim, then, species are, like most things that are historically and spatially contingent, particulars. Some species are also functionally cohesive (see Richard Boyd’s Homeostatic Property Cluster conception), but not all. And all species are phenomenal clusters. However, species can be multiply realised, have multiple origins of the genetic clusters that maintain them (incomplete lineage sorting) and so I think the functional notion of individuals is illictly imported from notion about organisms (and superorganisms), Some cluster are just accidental.

All and some are doing a lot of work here. While all is pretty precise, some can cover a couple through to most or nearly all. It may be that most species are accidentally formed. It may be they are accidentally maintained. It may be most are in fact functional clusters. This depends on the scope of the predicable here: do we apply terms for taxa to single celled organisms? Viruses? Obligate mutualists like lichens? If not, then we can define species into cohesive existence. If we do, then species are not all cohesions or systems.

Michael did a lot more than this. His book The economy of nature and the evolution of sex (1974) presented a sociobiology of his own, neither E. O. Wilson’s nor anyone else’s. And with Olaf Briedbach, he published some excellent history.

Ghselin’s books

Ghiselin, Michael T. 1969. The Triumph of the Darwinian Method. Berkeley: University of California Press.

———. 1974. The Economy of Nature and the Evolution of Sex. Berkeley: University of California Press.

———. 1984. The Triumph of the Darwinian Method, with a New Preface. Rev. Chicago: University of Chicago Press.

———. 1989. Intellectual Compromise: The Bottom Line. New York: Paragon House.

———. 1997. Metaphysics and the Origin of Species. Albany: State University of New York Press.

Some other of his papers

Breidbach, Olaf, and Michael T. Ghiselin. 2002. “Lorenz Oken and Naturphilosophie in Jena, Paris and London.” Hist. Phil. Life Sci. 24:219–47.

———. 2006. “Athanasius Kircher (1602–1680) on Noah’s Ark: Baroque ‘Intelligent Design’ Theory.” Proceedings of the California Academy of Science 57 (36): 991–1002. Cal Academy copy.

Ghiselin, M. T. 2004. “Mayr and Bock versus Darwin on Genealogical Classification.” Journal of Zoological Systematics and Evolutionary Research 42 (2): 165–69. https://doi.org/10/fbnprm.

Ghiselin, Michael T. 1966a. “An Application of the Theory of Definitions to Systematic Principles.” Systematic Zoology 15 (2): 127–30.

———. 1966b. “On Psychologism in the Logic of Taxonomic Controversies.” Systematic Zoology 15:207–15.

———. 1969. “The Distinction between Similarity and Homology.” Systematic Zoology 18 (1): 148–49.

———. 1974. “A Radical Solution to the Species Problem.” Systematic Zoology 23:536–44.

———. 1977. “On Paradigms and the Hypermodern Species Concept.” Systematic Zoology 26:437–38.

———. 1980. “Biogeographical Units: More on Radical Solutions.” Systematic Zoology 29:80–85.

———. 1984. “‘Definition,’ ‘Character,’ and Other Equivocal Terms.” Systematic Zoology 33:104–10.

———. 1985a. “Can Aristotle Be Reconciled with Darwin?” Systematic Zoology 34 (4): 457–60.

———. 1985b. “Mayr Versus Darwin on Paraphyletic Taxa.” Systematic Zoology 34 (4): 460–62. https://doi.org/10/cwnm2x.

———. 1987. “Species Concepts, Individuality, and Objectivity.” Biology and Philosophy 2:127–43.

———. 1988. “Species Individuality Has No Necessary Connection with Evolutionary Gradualism.” Systematic Zoology 37:66–67.

———. 1994a. “Darwin’s Language May Seem Teleological, but His Thinking Is Another Matter.” Biology and Philosophy (Historical Archive) 9 (4): 489.

———. 1994b. “The Imaginary Lamarck: A Look at Bogus ‘History’ in Schoolbooks.” The Textbook Letter, no. September-October, http://www.textbookleague.org/54marck.htm.

———. 1995. “Ostensive Definitions of the Names of Species and Clades.” Biology and Philosophy 10 (2): 219–22.

———. 1997. “Life’s Splendid Drama – Evolutionary Biology and the Reconstruction of Life’s Ancestry 1860-1340 – Bowler, PJ.” Pubblicazioni Della Stazione Zoologica Di Napoli – Section II: History and Philosophy of the Life Sciences 2:279–84.

———. 1998. “Etiological Classification and the Acquisition and Structure of Knowledge.” Behavioral and Brain Sciences 1:72 ff.

———. 2001. “Evolutionary Synthesis Frm a Cosmopolitan Point of View: A Commentary on the Views of Reif, Junker and Hossfeld.” Theory in Biosciences 120:166–72.

———. 2005. “Homology as a Relation of Correspondence between Parts of Individuals.” Theory in Biosciences 124 (2): 91–103. https://doi.org/10.1007/bf02814478.

———. 2006. “The Failure of Morphology to Contribute to the Modern Synthesis.” Theory in Biosciences 124 (3–4): 309–16.

———. 2007. “Is the Pope a Catholic?” Biology and Philosophy 22 (2): 283–91.

———. 2009a. “Darwin and the Evolutionary Foundations of Society.” Journal of Economic Behavior & Organization 71 (1): 4–9.

———. 2009b. “Metaphysics and Classification: Update and Overview.” Biological Theory 4 (3): 253–59. https://doi.org/10.1162/biot.2009.4.3.253.

Ghiselin, M.T. 2002. “Species Concepts: The Basis for Controversy and Reconciliation.” Fish and Fisheries 3 (3): 151-160(0).

Some discussions of the idea of individuality

Gayon, Jean. 1996. “The Individuality of the Species: A Darwinian Theory? – From Buffon to Ghiselin, and Back to Darwin.” Biology and Philosophy 11:215–44.

Kitcher, Philip. 1987. “Ghostly Whispers: Mayr, Ghiselin, and the ‘Philosophers’ on the Ontological Status of Species.” Biology and Philosophy 2 (2): 184–92. https://doi.org/10.1007/BF00057962.

Queiroz, Kevin de. 1995. “The Definitions of Species and Clade Names: A Reply to Ghiselin.” Biology and Philosophy 10 (2): 223–28.