And all this science I don't understand...

...It's just a job, five days a week. William Shatner sings Rocket Man. (HT: Cosmic Variance) Shatner once said, "Music is one of the most important parts of my life. Unfortunately, I can't sing." It's nice to know that inability isn't necessarily an impediment to doing things. Shatner's best bit of comedy, of course, is his parody of the Molson commercials with the "I Am Canadian" rant.

The Ever-Changing Blogosphere

A number of science bloggers I read (regularly or occasionally) are setting up shop at ScienceBlogs; notables from my sidebar are Chris at Mixing Memory and Coturnix at Science and Politics, who is combining several of his blogs into one, A Blog Around the Clock. ScienceBlogs isn't a mere addition to the blogosphere; it's a revolution, since it is changing how a small but formidable portion of the blogosphere works. HNN has, for quite a while, served a similar function for history blogging, but in a much smaller and less sleekly packaged way.

After a long period in which it had fallen into serious neglect, the TTLB Ecosystem has finally been reworked, with an expanded set of features. At present Siris is ranked #3439 in the Ecosystem (the rank changes as incoming links fluctuate). That's middling for the ecosystem as a whole, but very respectable for a blog that does not participate in any ecosystem community.

I'm currently working on developing a link archive for the Philosophers' Carnival. I have a number of ideas that I'll be trying out for it, but I'm also open to suggestions. The idea at present is just to provide a bit of redundancy for back-up purposes: twice now former hosts have closed down their blogs completely, thus sending the edition of the carnival that they hosted into oblivion. Richard caught one of them in time to be able to reconstruct it from Google cache; but the more recent case, the 19th carnival (at Mathetes), seems to exist no more. I'll be trying to reconstruct it out of fragmentary mentions\. If you had a post in that carnival, let me know.

An Active and Vital Energy

Were not sense and knowledge entirely different, we should rest satisfied with sensible impressions, such as light, colours and sounds, and inquire no further about them, at least when the impressions are strong and vigorous: whereas, on the contrary, we necessarily desire some further acquaintance with them, and can never be satisfied till we have subjected them to the survey of reason. Sense presents particular forms to the mind, but cannot rise to any general ideas. It is the intellect that examines and compares the presented forms, that rises above individuals to universal and abstract ideas; and thus looks downward upon objects, takes in at one view an infinity of particulars, and is capable of discovering general truths. Sense sees only the outside of things, reason acquaints itself with their natures. Sensation is only a mode of feeling in the mind; but knowledge implies an active and vital energy in the mind.

Richard Price, Review of the Principal Questions in Morals (1757) p. 16.

Links

* Elizabeth Anscombe's Contraception and Chastity can be read online. Besides the topics in its title, it also clarifies some misconceptions about natural law. It also comes with responses and Anscombe's reply to those responses.

* The BBC has a happiness test. My score:

Highly satisfied
People who score in this range love their lives and feel that things are going very well. Your life is not perfect, but you feel it is about as good as life gets. Furthermore, just because you are satisfied does not mean you are complacent. In fact, growth and challenge might be part of the reason you are satisfied. For most people in this high-scoring range, life is enjoyable, and the major domains of life are going well - work or school, family, friends, leisure, and personal development.

* Scott McLemee interviews Ophelia Benson at Inside Higher Ed. She's rather vague, but makes considerable sense.

* Gordon Marino has an article on boxing and philosophy at The Chronicle of Higher Education.

* Jeremy Pierce has a post on a recent piece in The Huffington Post. He defends Campus Crusade for Christ against a recent smear, but the argument is more generally about a certain type of ghoulishness that is eager to call good evil.

->Blogger is still acting badly. This is the worst it's been since Google took over; I wonder what's going on.

Zadig

Cuvier, speaking of how a biologist can deduce the nature of the animal from the slightest clues:

But I doubt if any one would have divined, if untaught by observation, that all ruminants have the foot cleft, and that they alone have it. I doubt if any one would have divined that there are frontal horns only in this class: that those among them which have sharp canines for the most part lack horns.

However, since these relations are constant, they must have some sufficient cause; but since we are ignorant of it, we must make good the defect of the theory by means of observation: it enables us to establish empirical laws, which become almost as certain as rational laws, when they rest on sufficiently repeated observations; so that now, whoso sees merely the print of a cleft foot may conclude that the animal which left this impression ruminated, and this conclusion is as certain as any other in physics or morals. This footprint alone, then, yields to him who observes it, the form of the teeth, the form of the jaws, the form of the vertebræ, the form of all the bones of the legs, of the thighs, of the shoulders, and of the pelvis of the animal which has passed by: it is a surer mark than all those of Zadig.

[Quoted in T. H. Huxley, An Introduction to the Classification of Animals (1869)]

The allusion in the last sentence is to Voltaire's delightful little work, Zadig, a favorite of semioticians and people interested in the pre-history of detective fiction. If you haven't read it, you should; Project Gutenberg has an English translation.

Darwin on Natural Classification

One of my favorite passages in the Origin of Species (chapter 13):

Naturalists try to arrange the species, genera, and families in each class, on what is called the Natural System. But what is meant by this system? Some authors look at it merely as a scheme for arranging together those living objects which are most alike, and for separating those which are most unlike; or as an artificial means for enunciating, as briefly as possible, general propositions, that is, by one sentence to give the characters common, for instance, to all mammals, by another those common to all carnivora, by another those common to the dog-genus, and then by adding a single sentence, a full description is given of each kind of dog. The ingenuity and utility of this system are indisputable. But many naturalists think that something more is meant by the Natural System; they believe that it reveals the plan of the Creator; but unless it be specified whether order in time or space, or what else is meant by the plan of the Creator, it seems to me that nothing is thus added to our knowledge. Such expressions as that famous one of Linnaeus, and which we often meet with in a more or less concealed form, that the characters do not make the genus, but that the genus gives the characters, seem to imply that something more is included in our classification, than mere resemblance. I believe that something more is included; and that propinquity of descent, the only known cause of the similarity of organic beings, is the bond, hidden as it is by various degrees of modification, which is partially revealed to us by our classifications.

He argues this point throughout the chapter. We know that Darwin read Whewell; and we also know that some of Darwin's own conception of science was influenced by Whewell, although there appears to be no consensus as to the extent of that influence. But whether Darwin is influenced by Whewell here or not, he is inserting the theory of natural selection into an important set of questions about natural classification that had been discussed at some length by scientists of the period. Like Whewell, Darwin thinks we need more than mere resemblance to establish the natural system. On Whewell's proposal the 'something more' is the natural affinities of organisms as whole organic systems. On Darwin's proposal the 'something more' is propinquity of descent. Despite the differences, there are very important similarities: they both point out that resemblance accounts eventually must start distinguishing important functions from unimportant ones, and they both hold that the only way to do this in a non-arbitrary way is to appeal to constancies based on conditions of existence. Because they have different proposals, the constancies they appeal to are slightly different -- Whewell's constancy is internal, whereas Darwin's is comparative. But their criticisms of resemblance-only accounts are kin.

It's possible, in fact, to see Darwin's proposal as simply a larger proposal that embraces Whewell's own -- i.e., to see Darwin as taking Whewell's position and subsuming it. Darwin explicitly proposes descent with modification as the explanation for natural affinity:

All the foregoing rules and aids and difficulties in classification are explained, if I do not greatly deceive myself, on the view that the natural system is founded on descent with modification; that the characters which naturalists consider as showing true affinity between any two or more species, are those which have been inherited from a common parent, and, in so far, all true classification is genealogical; that community of descent is the hidden bond which naturalists have been unconsciously seeking, and not some unknown plan of creation, or the enunciation of general propositions, and the mere putting together and separating objects more or less alike.

That is, insofar as natural affinity is a matter of arrangement, it is a matter of propinquity of descent. (Insofar as it is a matter of closeness of resemblance, it is dependent on the contingencies of modification.) Darwin points out that, to an extent, naturalists have to bring propinquity of descent into the natural system anyway: species by their very definition have propinquity of descent. So Darwin is not proposing something completely alien to the naturalist's attempt to classify: he is proposing that naturalists expand something they have always done. Indeed, he goes farther than that, suggesting that unconsciously naturalists often appealed to descent for much of the rest of their classification. Like the vague conception of natural affinity we find Whewell attributing to natural historians, this unconscious appeal to descent serves both to connect the proposed account to actual natural-historical practice and, perhaps more interestingly, is said to account for the actual results of natural history. In other words, just as Whewell argues that the classifications of natural historians are already based on natural affinity, however vague and confused the conception of it sometimes has been, so Darwin argues that they are already based on descent, however 'unconscious' and confused its role in the classification has been:

I believe this element of descent is the hidden bond of connexion which naturalists have sought under the term of the Natural System. On this idea of the natural system being, in so far as it has been perfected, genealogical in its arrangement, with the grades of difference between the descendants from a common parent, expressed by the terms genera, families, orders, &c., we can understand the rules which we are compelled to follow in our classification. We can understand why we value certain resemblances far more than others; why we are permitted to use rudimentary and useless organs, or others of trifling physiological importance; why, in comparing one group with a distinct group, we summarily reject analogical or adaptive characters, and yet use these same characters within the limits of the same group. We can clearly see how it is that all living and extinct forms can be grouped together in one great system; and how the several members of each class are connected together by the most complex and radiating lines of affinities.

In comparing Darwin's view with Whewell, I don't want to imply that Darwin is necessarily thinking of Whewell (among others) in this argument, although that is very possible. But Whewell, as is fitting the father of the philosophy of science, is very careful to make base his philosophy of the classificatory sciences on things that had been learned and proposed by natural historians themselves; although he clarifies, refines, and develops ideas, he is primarily cleaning up in order to show clearly the state of the field in his time. Whewell is able to bring classification in natural history up to natural affinity; Darwin goes farther, and proposes to explain even natural affinity by descent with modification. In so doing he sets the notion of natural classification in biology on a new basis. (Of course, it is important to remember that biological natural history is not the only classificatory science. Whewell had a special interest in mineralogy, and, in fact, much of his actual scientific work was in improving mineralogical classification. As a general account of natural systems, Whewell's Idea of Natural Affinity is still necessary; descent with modification only explains natural affinity for natural systems that are genealogical in origin.)

For a discussion of how natural classification was understood by nineteenth-century natural historians after Darwin, see Robert O'Hara's paper on the subject.

Typology and Natural Classification

One of the more interesting aspects of Whewell's theory of natural classification is his argument that natural classes are to be fixed not by definition by by type. The general line of thought is very nicely summarized in Whewell's aphorisms (vol. 2, p. 460-461):

XCII. Natural Groups are best described, not by any definition which marks their boundaries, but by a Type which marks their center. The Type of any natural group is an example which possesses in a marked degree all the leading characters of the class. (VIII. 2.)

XCIII. A Natural Group is steadily fixed, though not precisely limited; it is given in position, though not circumscribed; it is determined, not by a boundary without, but by a central point within;--not by what it strictly excludes, but by what it eminently includes;--by a Type, not by a Definition. (VIII. 2.)

XCIV. The prevalence of Mathematics as an element of education has made us think Definition the philosophical mode of fixing the meaning of a word: if (Scientific) Natural History were introduced into education, men might become familiar with the fixation of the signification of words by Types; and this process agrees more nearly with the common processes by which words acquire their significations. (VIII. 2.)

It might be helpful to look at the argument behind aphorism XCII in a bit more detail. Whewell argues that definitions in natural history will tend to become indefinite and inconsistent; definitions are quite OK for abstract sciences, but natural history is concerned with classifying actual, concrete things, which admit of considerable variation. We might think that this means that the classes established by natural history are "quite loose, without any certain standard or guide," but it is not actuall so (vol. 1, p. 494). As Whewell puts it (vol. 1, p. 494):

The class is steadily fixed, though not precisely limited; it is given, though not circumscribed; it is determined, not by a boundary line without, but by a central point within; not by what it strictly excludes, but by what it eminently includes; by an example, not by a precept; in short, instead of a Definition we have a Type for our director.

A type is an idealized example of a class: one that eminently possesses all the characters of the class. Other types are ranged around it, deviating from it in various degrees and in various ways. This forms our classification. And, as Whewell notes, the fact that there might be some species whose relations to a type are hard to determine doesn't change the general effectivenessness of the classification as a whole, any more than scattered trees between two hills makes it impossible to talk rationally about two different forests on two different hills.

An example of type-based classificationThe type of the rose family has alternate stipulate leaves, no albumen, non-erect ovules, simple stigmata, and so forth. It is entirely possible for individual roses to break this pattern without ceasing to be roses. But while individual roses vary around it, the type forms a center for all the variation. It's as if you shot a paintball at a target: the type is the point in the center, and the variants are the splatter around it.