Evolving Thoughts

Evolution, culture, philosophy and chocolate! John Wilkins' continuing struggle to come to terms with impermanence... "Humanus sum, nihil humanum a me alienum puto" - Terence

Thursday, February 17, 2005

A fine and privative place

Officials Warn of Future Terror Attacks: "Director Robert Mueller expressed worry that a sleeper operative in the U.S. may have been in place for years, awaiting orders for an attack.

'I remain very concerned about what we are not seeing,' Mueller said in remarks he submitted to the senators."
What we are not seeing is the sort of attack on our way of life that the hysterical have claimed we will see. It is a problem if you are trying to get funding for a multi-trillion dollar war, the primary purpose of which is to bolster support for a particular government and political party. So of course you have to say that the absence of evidence of this terrorist threat to American and western society in general is evidence that it is happening.

Terrorism is a fairly economical way to fight a war - you have only to cause dramatic harm to some small number of people, and the target country does the rest of the harm for you. What we have witnessed is trillions of dollars/pounds being spent to fight a war while the west becomes the sort of narrow-minded and religiously intolerant society that the terrorists themselves live in. We have met the Taliban, and it is us.

They hate secularism. They are much more comfortable dealing with a society like their own - the stakes and gambits are much clearer. So abandoning secularism, open society, and rule of law the way we have done is playing right into their hands. Modernism is the enemy. If we abandon it, they win, even if they lose.

But that is not why this blog entry. I am amused by the privative nature of the comment. Privation, as I'm sure you all learned in grade school, is classification of a group of things, or the definition of a class, in terms of what they are/it is not. Of course, this causes some trouble. It is no coincidence that William Dembski's "Explanatory Filter" that allows one to conclude life was designed specifies "design" as a privative class (the "set-theoretic complement of the disjunction of regularity-or-chance", Design Inference p50; thanks to Sahotra Sarkar for the ref). Basically, "design" is just everything that is not something else - in this case, explanation by law or chance.

The problem with privative categories is that they are massively sensitive to what you expect. If you expect terrorism, then of course a lack of it is worrying. If you expect that everything is a vertebrate, then everything else is an invertebrate, as Lamarck defined them. But as Nelson and Platnick observe in a much-underappreciated book, rocks are not vertebrates. Are they invertebrates? If you don't think so, ask what you expected to be included in the wider group that "vertebrates" are selected out of. Is is Life? Multicellular organisms? Animals? Now justify the choice of that particular wider category.

Aristotle knew about this. In the The History of Animals, he discusses why privative terms are not proper to classification (book I, chapter 3):
… privative terms inevitably form one branch of dichotomous division, as we see in the proposed dichotomies. But privative terms in their character of privatives admit of no subdivision. For there can be no specific forms of a negation, of Featherless for instance or of Footless, as there are of Feathered and of Footed. Yet a generic differentia must be subdivisible; for otherwise what is there that makes it generic rather than specific? There are to be found generic, that is specifically subdivisible, differentiae; Feathered for instance and Footed. For feathers are divisible into Barbed and Unbarbed, and feet into Manycleft, and Twocleft, like those of animals with bifid hoofs, and Uncleft or Undivided, like those of animals with solid hoofs. Now even with differentiae capable of this specific subdivision it is difficult enough so to make the classification, as that each animal shall be comprehended in some one subdivision and in not more than one; but far more difficult, nay impossible, is it to do this, if we start with a dichotomy into two contradictories. (Suppose for instance we start with the two contradictories, Feathered and Unfeathered; we shall find that the ant, the glowworm, and some other animals fall under both divisions.) For each differentia must be presented by some species. There must be some species, therefore, under the privative heading. Now specifically distinct animals cannot present in their essence a common undifferentiated element, but any apparently common element must really be differentiated. (Bird and Man for instance are both Twofooted, but their two-footedness is diverse and differentiated. So any two sanguineous groups must have some difference in their blood, if their blood is part of their essence.) From this it follows that a privative term, being insusceptible of differentiation, cannot be a generic differentia; for, if it were, there would be a common undifferentiated element in two different groups.
Stripped of the logical phrasing Aristotle invented, in effect he is saying that if you have a privative classification, then you have no simple and clear way to exclude all kinds of things. And that is why I am saying that what remains once the positive class is excluded from the wider set depends entirely on what you expect to see in the first place. It's subjective and arbitrary.

I know this is a long way from terrorism, but the rules of logic are universal (arguably). We ought to worry about what we actually do see, not what we might not see. As I look around, I see the loss of traditional rights, the inclusion of religious conviction into public policy and the consequent imposition of that conviction on others, the control of the media and the debate by those in power... all the kinds of things that once caused a revolution in a certain nation.

Power corrupts. One of the things it corrupts is debate.

Nelson, Gareth J., and Norman I. Platnick. 1981. Systematics and biogeography: cladistics and vicariance. New York: Columbia University Press.


Evolution Revolution in Arizona: Damn those professors!

The Tucson Weekly is reporting the complaints of a Republican Senator that she nearly got a bill through the state legislature compelling teachers "to present evidence that supports and evidence that does not support the theory of evolution" until those damned university perfessors intervened.

What was the giveaway here that something might be troublesome? The fact that the scientists and specialists who spend their lives studying biology and evolution think there simply is no such evidence? Or the fact that the support for the bill came from "a flood of supportive e-mails"?

We face today a rising inclination for public policy makers to pander to the lowest common denominator. Don't like that science? It's wrong, so teach this. Don't like this part of history, whether it is PC or not? Then change the schoolbooks, the curriculum and the media presentations to avoid unpleasantness. Hey, it works for Japan.

Tuesday, February 15, 2005

Flogic - a new modal logic

I have made an amazing discovery of a new modal logic. I was analysing the structure of the argument used by the new Design Theorists, in particular William Dembski's Explanatory Filter, which I have discussed in print, when I realised, with the help of chemist Paul Gans of NYU, that it all made amazing sense if you assume a novel logical operator. Once I realised this, I found that it also works extremely well in military and public policy issues.

I call the operator "floogle", and devised this representation for logical equations:

Floogle is the "possibly-therefore-true" operator. It is possible that life was made by an intelligent design (despite the complete lack of any reason to think so), therefore it was. It is possible Iraq had WMDs, therefore they did. It is possible that Clinton was a sleeper spy for the Communist Chinese, therefore he was. And so forth. This simple logical modal operator is the greatest contribution to discovery methods since the doctrine of signatures.

I will now sit back and wait for those awards...

Sunday, February 13, 2005

Mayr's Whig

The evil that men do lives after them;

The good is oft interred with their bones;

So let it be with Caesar.

After a decent period to mourn the death of one of the greatest biologists of the century on any measure, perhaps it is time now to reassess how Mayr's legacy is to be presented. I have no competence to debate his scientific ideas - if speciation is mostly allopatric, or if it is sympatric, or something else, that is not a philosophical matter. If gene flow maintains the integrity of a species, this will be established at last by empirical and theoretical studies, and not a priori analysis.

But how Mayr used history is a matter for discussion outside science. In addition to the usual historiographical considerations, there is also the matter of how scientists use history in their scientific endeavors.

A cardinal sin in history is sometimes referred to as "presentism", to treat the present as the measure of the past, morally or intellectually. It has other names as well - anachronism, modernism, and so forth - but the label most often used derives from an influential book by the historian, appropriately, of science, Herbert Butterfield, published in 1931. It was titled The Whig Interpretation of History.

The term "whig interpretation" preceded Butterfield's use of it. It literally meant the way whigs - later the "liberal" side of British politics, although they were as often as not illiberal - who sided with Protestantism against Catholics, read their history. What Spain or France did was wrong, and what Protestant Germany did was right, and England (oops, Britain) was always on the side of progress and the modernisation of the world.

Mayr, in his Growth of Biological Knowledge is aware of this sin, for he discusses it on pages 11-13. He notes that "[t]he history of biology is rich in such biased whig interpretations" (p12). Nevertheless, the "interests of a historian necessarily influence his decision as to which subjects to treat in detail and which others in a more cursory fashion." He quotes a 1911 historian of physics who preferred, he said, "to be frankly subjective".

But selective treatment and cursoriness is one thing. Treating that which is past as the precursor of some favorite modern theory is quite another, and selectively quoting sources to give an impression that is wrong or at best unsupported is intellectual dishonesty. Did Mayr do this? I think so, and here are the cases where it matters to my research.

Some background, first. Mayr's claim is that "species" in biology refers, as we famously know, to

... a group of population which replace each other geographically or ecologically and of which the neighboring ones intergrade or interbreed wherever they are in contact or which are potentially capable of doing so (with one or more of the populations) in those cases where contact is prevented by geographical or ecological barriers.

Or shorter: Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups. [Mayr 1940 p120]

So Mayr seeks in his writings to establish not only that this is a viable conception of the term "species", which has a history back to the late middle ages as a term of botanical and zoological classification, but that it is the "goal" towards which biologists before him were striving. If it were true, then this would not be a problem. It is not true.

In general terms, species had a reproductive component of interbreeding at various times since antiquity, particularly in Lucretius' poem On The Nature of Things, which faithfully reproduced the earlier ideas of Epicurus, whose own writings have only survived as fragments. The notion that Mayr's "discovery" represents some novelty is less clear than presented. But we are here considering how Mayr himself treats his sources and the history. So let us turn to that. In a 1996 work, Mayr said
Even though this [essentialistic and typological concept] was virtually the universal concept of species, there were a number of prophetic spirits who, in their writings, foreshadowed a different species concept, later designated [by Mayr, as it happens – JSW] as the biological species concept (BSC). The first among these was perhaps Buffon (Sloan 1987 [1985 - JSW]), but a careful search through the natural history literature would probably yield quite a few similar statements. [p269]
Collingwood (1946) noted that such approaches to history as the progressive leading-up to the modern day or some ideal state have been viewed askance by historians:
Bach was not trying to write like Beethoven and failing; Athens was not a relatively unsuccessful attempt to produce Rome; Plato was himself, not a half-developed Aristotle [p329]

and, we might add, the writers on species in the period in question were not precursors to Ernst Mayr. There has always been a "biological" (reproductive) component to discussions of species as applied to the living world, which I call the "generative" notion of species. Moreover, few of the writers adduced by Mayr as forerunners actually are presenting anything much like his view, as most of them include a clear morphological component in their conceptions (which is the other half of the generative conception).

Nevertheless, Mayr’s claim of E. B. Poulton and K. Jordan as "precursors" would seem to be fair, at least in terms of a similarity of views, and given the number of times he cites them, he may even have them as direct antecedents – that is, they might have directly influenced him. Erwin Stresemann, as his teacher, clearly did (Chung 2003; Winsor 2003).

Although this may sound harsh, Mayr does referred to his "precursors" as "prophetic spirits" (Mayr 1996, p269), noting "how tantalizingly close to a biological species concept some of the earlier authors had come" (Mayr 1982, p271), and claimed that "Buffon understood the gist of it" and the early Darwin also (Mayr 1997, p130), thus claiming authoritative precursors. Hull (1988, pp372–377) discusses the role precursors play in scientific histories. One function for precursors is to give legitimacy to the views of the modern scientist and deflect criticism to dead white males. Similar things happened with Galileo, and also with the "rediscoverers" of Mendel.

More worrying is how Mayr treated at least one source, doctoring the quote to present himself as the fulfilment of the concerns of a precursor. Buffon is perhaps the most significant of the pre-evolutionary biologists - he influenced not only Lamarck but also Cuvier, and he introduced, in the course of a rambling 36 volume work (eight more volumes being added after he died), the Histoire naturelle, a multitude of ideas and terms that found their way into modern biology. Two animals are of the same species, he wrote in the second volume of the Histoire naturelle (Lovejoy 1959: 93f),
... if, by means of copulation, they can perpetuate themselves and the likeness of the species; and we should regard them as belonging to different species if they are incapable of producing progeny by the same means. Thus the fox will be known to be a different species from the dog if it proves to be a fact that from the mating of a male and female of these two kinds of animals no offspring is born; and even if there should result a hybrid offspring, a sort of mule, this would suffice to prove that fox and dog are not of the same species – inasmuch as this mule would be sterile (ne produirait rien). For we have assumed that, in order that a species might be constituted, there was necessary a continuous, perpetual and unvarying reproduction (une production continue, perpétuelle, invariable) – similar, in a word, to that of other animals.
Intriguingly, Mayr (1982: 334) omits the last sentence, although he is quoting from Lovejoy's book as I am. Why? It is because, I think, of Mayr's long-standing attack on the use of morphology as a defining feature of species. If Buffon treated morphology as a definiens of species, then he is useless as a precursor. Mayr needs to find those who agree with him, albeit incompletely. It is no good to find that morphology and reproduction are combined.

Everywhere I looked, however, I found that morphology and reproduction were the defining criteria for conspecificity. Mayr's simplified conception of species before the favored precursors being purely morphological and hence essentialistic is just wrong. So he is downplaying the generative conception in order to offer his own view[s] as more novel.

This is, on any account of historiography, dishonest. It systematically skews the history of important ideas in science. I know why Mayr does it - this is, indeed, a consistent problem when textbooks write history - but in a putatively historical book, the one most people use when studying the history of biology, it is unforgiveable. It is a sin among the prohibitiva, sins against the Holy Spirit, although here that spirit is Clio. Scientists write history for a polemical purpose. Treat what they say with great care.

Incidentally, this is part of a larger issue I attack in my work on species, which, if it ever gets published, will include this. The Received View on species, is just plain false. It is not false because dishonest people falsified it, but because scientists are not historians as such, and tend to think, as we all do, that if you go looking for something, and find it, it is there. Historians, of course, have a different agenda - to find what is there independent of expectations.

Anyone who is looking for a useful and generally reliable history of biology is advised to find Lois Magner's A history of the life sciences (second edition) or Erik Nordenskiöld's older history, which is more detailed but less reliable for events recent to him, such as Darwinism. Charles Singer's 1959 edition is also very good.

References

Butterfield, Herbert. The Whig Interpretation of History. London: G. Bell, 1931.

Chung, Carl. "On the Origin of the Typological/Population Distinction in Ernst Mayr's Changing Views of Species, 1942–1959." Studies in History and Philosophy of Biological and Biomedical Sciences 34 (2003): 277-296.

Collingwood, R. G. The Idea of History. 1961 Paperback ed. Oxford: Oxford University Press, 1946.

Hull, David L. Science as a Process: An Evolutionary Account of the Social and Conceptual Development of Science. Chicago: University of Chicago Press, 1988.

Lucretius. On the Nature of Things (De Rerum Natura). Translated by Martin Ferguson Smith. London: Sphere Books, 1969.

Magner, Lois N. A History of the Life Sciences. 2nd ed. New York: Marcel Dekker, Inc., 1994.

Mayr, Ernst. "Speciation Phenomena in Birds." American Naturalist 74 (1940): 249-278.

---. "What Is a Species, and What Is Not?" Philosophy of Science 2 (1996): 262–277.
---. The Growth of Biological Thought: Diversity, Evolution, and Inheritance. Cambridge, Mass.: Belknap Press, 1982.
---. This Is Biology: The Science of the Living World. Cambridge, Mass.: Belknap Press of Harvard University Press, 1997.

Nordenskiöld, Erik. The History of Biology: A Survey. Translated by L. B. Eyre. London: Kegan Paul, Trench, Trubner and Co, 1929.

Singer, Charles Joseph. A History of Biology to About the Year 1900: A General Introduction to the Study of Living Things. 3rd ed. London: Abelard-Schuman, 1959.

Sloan, Phillip R. "From Logical Universals to Historical Individuals: Buffon's Idea of Biological Species." In Histoire Du Concept D'espece Dans Les Sciences De La Vie, 101-140. Paris: Fondation Singer-Polignac, 1985.

Winsor, Mary Pickard. "Non-Essentialist Methods in Pre-Darwinian Taxonomy." Biology & Philosophy 18 (2003): 387-400