Eight Little Piggies
Second, just as young Mozart could separate and abstract single emotions, Darwin realized that standard facial gestures must be modules of largely independent action—and that the human emotional repertoire must be more like the separate items in a shopper’s bag than the facets of an unbreakable totality. Evolution can mix, match, and modify independently. Otherwise we face Cuvier’s dilemma: If all emotions are inextricably bound by their status as interacting, optimal expressions, then how can anything ever change?
Late in his life, Darwin wrote an entire book on this subject: The Expression of the Emotions in Man and Animals (1872). But his youthful jottings in the so-called M Notebook of 1838, hastily scribbled in the months before he codified his theory of natural selection in September of the same year, are even more compelling for their telegraphic expression of excitement in discovery and novel explanation. Darwin later labeled this notebook as “full of Metaphysics on Morals and Speculations on Expression.” His fascinating notes on emotional gestures center on modularity and its importance for evolutionary explanation. Each feeling is linked to a gesture; we have limited control over the form of a gesture, and its evolutionary meaning must often be sought in a lost ancestral function. Darwin wrote:
He may despise a man and say nothing, but without a most distinct will, he will find it hard to keep his lip from stiffening over his canine teeth.—He may feel satisfied with himself, and though dreading to say so, his step will grow erect and stiff like that of turkey…. With respect to sneering, the very essence of an habitual movement is continuing it when useless,—therefore it is here continued when uncovering the canine useless.
Darwin then speculates on the further evolution of emotions treated as separate entities. He argues that sighing is still directly useful in humans “to relieve circulation after stillness.” Yet we might retain the gesture as a sign for an accompanying emotion even if the physiological benefit disappeared: “If organization were changed, I conceive sighing might yet remain just like sneering does.”
I received my clearest insight into the modularity of facial expressions not from any scientific writing, but from viewing the world’s greatest sculpture: Michelangelo’s Moses in the church of San Pietro in Vincoli (St. Peter in Chains) in Rome. Moses, bearing the tablets of the ten commandments, has just come down from Mount Sinai. Suffused with holiness, and with joy at the gift he may now bestow upon his people, he looks around only to see the Israelites worshipping the golden calf. His face is a maelstrom of emotions: zeal and ardor for what he has witnessed on the mountain, rage at his people for their transgression, deep sorrow for human weaknesses. The sublimity of the statue lies in the richness of this mixture upon one face—as if Moses has become everyman (in every major state of feeling).
I visited this statue several times and felt its power but could not grasp how Michelangelo had put so much into one face. On my last trip, and largely by chance, I think that I found a guide to the solution. Michelangelo understood—whether viscerally or explicitly, I do not know—the principle of modularity. When I focused on one feature and covered the rest of the face, I saw only one emotion each time. The eyebrows speak one message, the nose another, the lips a third. The rich face can be decomposed into modules of feeling, but the totality stuns us by integration.
Many of the most famous experiments in animal ethology affirm and extend the principle of modularity. Consider Niko Tinbergen’s classic work on begging for food in newly hatched gulls (so beautifully described in his charming book, The Herring Gull’s World). The newborns peck vigorously at their parents’ beak, apparently aiming for a red spot near the tip of the mandible. If an infant makes proper contact, the parent regurgitates a parcel of food and the baby gull gets its first meal.
But what inspires the pecking behavior? The baby gull has no conscious understanding of a reward to be gained. It has never eaten before and cannot know what a knock on a parent’s bill will provide. The behavior must be innate and unlearned.
At what, then, does the baby bird direct its pecks? At first consideration, one might conjecture that the entire form or gestalt of the parent would provide an optimal target. After all, what could be more appealing than the parent’s totality—a full, three-dimensional image with the right movements and odors. But consider the issue a bit more deeply: The hatchling has never seen a bird. Can the complexities of the entire parental form be engrafted innately upon its untested brain? Wouldn’t the goal be more readily achieved—easier to program if you will—if the hatchling responded to one or a few abstract particulars, that is, to modules extracted from the total form?
In an exhaustive series of experiments, Tinbergen showed that hatchling gulls do respond to modules and abstractions. They peck preferentially at long and skinny objects, red things, and regions of markedly contrasting colors. As an effect of this simplified modularity, they hit the spot at the tip of the parental bill—the only red region at the end of a long object, in an area of contrasting color with surrounding yellow. Complex totality may be beyond the cognitive capacity of a hatchling gull, but any rich object can be broken down to simpler components and then built up. Any developing complexity—whether in the cognitive growth of an individual or the evolution of a lineage—may require this principle of construction from modules.
If hatchling gulls favor abstractions (and don’t perceive parental totality), then Tinbergen reasoned that he might construct a “super-gull”—a model exaggerating the key modules. This “improved” version might elicit more attention than the actual parents themselves. This idea bore fruit as hatchlings preferred several remarkably artificial dummies to real birds. For example, narrow sticks longer than real bills, and color patches more starkly contrasted with surroundings than the red spot on an actual bill, elicited more pecks from hatchlings than did an accurately modeled head.
Tinbergen then generalized these observations to the important concept of a super-normal stimulus—an artificial exaggeration that elicits more favor or response than the feature itself. (In his book, Tinbergen includes an amusing discussion of his struggle to find a good name for this phenomenon. He first spoke of a super-optimal stimulus, but finally rejected the term as oxymoronic—for optima, by definition, cannot be exceeded. He then remarks that ‘supernatural’ would be a good term, if it were not used already in another sense.” Finally, he settled upon super-normal).
Many animals exploit this modular principle of super-normal stimuli to gain advantage over others. In the classical example, cuckoos subvert the propensities of their hosts to feed any chick in the nest that rises higher, squawks louder, or opens its beak wider. The mother cuckoo lays an egg in another bird’s nest. The egg itself is an accurate mimic and often can’t be distinguished from the host’s own products. But the cuckoo hatchling quickly outstrips its nestmates in growth and may even toss them out to their death. The unwitting adult hosts, fooled by the super-normal stimuli arising from the large, loud cuckoo chick, continue to feed the usurper and murderer.
Obviously, if modularity didn’t often rule over accurate perception of totalities, super-normal stimuli would not exist. Host parents would know their own children and reject the cuckoo. Hatchling gulls would peck at parental beaks (that might feed them), rather than at cardboard dummies with exaggerated features.
Modularity pervades all neurological organization, right up to what Darwin called “the citadel itself”—human cognition. This principle of breaking complexity into dissociable units does not disappear at the apex of known organization. Humans might not be fooled in toto by the analog of a cuckoo chick, but the fashion industry knows how well, and how sheepishly, we respond to a plethora of super-normal stimuli.
Interestingly, Darwin accompanied his M-notebook jottings on the modularity of emotional gestures with similar statements about cognitive items and units:
People who can multiply large numbers in their head must have this high faculty, yet not clever people…. The great calculators, from the confined nature of th
eir associations (is it not so in punning) are people of very limited intellects, and in the same way are chess players…. The son of a fruiterer in Bond St. was so great a fool that his father only left him a guinea a week, yet he was inimitable chess player.
The concept of modularity, explicitly so called, lies at the heart of much innovative research in cognitive science. The brain does a great deal of work by complex coordination among its parts, but we have also known for a long time that highly particular aptitudes and behaviors map to specific portions of the cerebral cortex. The modules are often stunningly precise and particular, as illustrated by unusual losses and misperceptions of people who have suffered damage to highly localized regions of cortex (see Oliver Sacks’ wonderful book, The Man Who Mistook His Wife for a Hat). The September 19, 1991, issue of Nature tells the remarkable story of two men who suffered localized strokes that seriously impaired their ability to use and recognize vowels but not consonants. Surely, we would have regarded our separation of sounds into vowels and consonants as an artificial division of a totality—yet this distinction may record a deeper mapping of cerebral modules.
Mozart was not yet Mozart when Daines Barrington witnessed his incredible performance. He was just a bratty kid at the acme of precocity. In fact, Barrington even speculated on his potential for future contributions. He spoke of another prodigy named John Barratier who knew Latin at four, Hebrew at six, and who translated the travels of Rabbi Benjamin, complete with learned notes and glosses, at eleven. But we know little of Barratier today because he died before the age of twenty.
Barrington notes the unhappy tendency of geniuses to die young, and he expresses his hope for Mozart by comparing him with England’s greatest musical guest, the German emigré Handel. Young Handel may not have been quite so precocious as Mozart, but he did live a long and remarkably productive life, from 1685 to 1759, and Barrington took comfort:
I am the more glad to state this short comparison between these two early prodigies in music, as it may be hoped that little Mozart may possibly attain to the same advanced years as Handel, contrary to the common observation that such ingenia praecocia are generally short lived.
Barrington got half his wish. Mozart lived long enough to become Mozart, but died so young, at thirty-five, that his early demise has become the canonical example of a genre—the tragic and uncertain lives led by so many artists. (I wrote this essay on the very day of the two hundredth anniversary of Mozart’s death. I wish that I had been able to compose this piece at the proper Handelian distance of forty years hence, which would have been good for Mozart and good for me too).
Daines Barrington thought that he was writing a scientific article about the modularity of human abilities. The later exaltation of Mozart makes us view his work in a more particular light—as a testimony about the early life of everyone’s favorite musical prodigy. Is Barrington’s article part of science or of art? Perhaps, for once, these are truly false modules, and our intellectual life would benefit by more integration. If Mozart had died before Mitridate (a teenage opera), Barrington’s article would endure as a respectable scientific account of a generic musical prodigy. I thank God for Don Giovanni (and I promise to tolerate every Musak rendition of Eine Kleine Nachtmusik in exchange). But even if Mozart had died in childhood, in the frosts of an English winter (in their damned buildings without central heating), his contribution to our understanding of the human mind would still be no mean thing, no small potatoes.
18 | The Moral State of Tahiti—and of Darwin
CHILDHOOD PRECOCITY is an eerie and fascinating phenomenon. But let us not forget the limits; age and experience confer some blessing. The compositions that Mozart wrote at four and five are not enduring masterpieces, however sweet. We even have a word for such “literary or artistic works produced in the author’s youth” (Oxford English Dictionary)—juvenilia. The term has always borne a derogatory tinge; artists certainly hope for substantial ontogenetic improvement! John Donne, in the second recorded use of the word (1633) entitled his early works: “Iuuenilia: or certaine paradoxes and problemes.”
I shouldn’t place myself in such august company, but I do feel the need to confess. My first work was a poem about dinosaurs, written at age eight. I cringe to remember its first verse:
Once there was a Triceratops
With his horns he gave big bops
He gave them to an allosaur
Who went away without a roar.
(I cringe even more to recall its eventual disposition. I sent the poem to my boyhood hero, Ned Colbert, curator of dinosaurs at the American Museum of Natural History. Fifteen years later, when I was taking his course as a graduate student, Colbert happened to clean out his old files, found the poem, and gleefully shared it with all my classmates one afternoon.)
Now, a trivia question on the same theme: What was Charles Darwin’s first published work? A speculation on evolution? Perhaps a narrative of scientific discovery on the Beagle? No, this greatest and most revolutionary of all biologists, this inverter of the established order, published his first work in the South African Christian Recorder for 1836—a joint article with Beagle skipper Robert FitzRoy on “The Moral State of Tahiti.” (The standard catalogue of Darwin’s publications lists one prior item—a booklet of Beagle letters addressed to Professor Henslow and printed by the Cambridge Philosophical Society in 1835. But this pamphlet was issued only for private distribution among members—the equivalent of an informal modern Xeroxing. “The Moral State of Tahiti” represents Darwin’s first public appearance in print, and biographers record it as his first publication—even though the article is mostly FitzRoy’s, with long excerpts from Darwin’s diaries patched in and properly acknowledged.)
The great Russian explorer Otto von Kotzebue had poured fuel on an old and worldwide dispute by arguing that Christian missionaries had perpetrated far more harm than good in destroying native cultures (and often cynically fronting for colonial power) under the guise of “improvement.” FitzRoy and Darwin wrote their article to attack Kotzebue and to defend the good work of English missionaries in Tahiti and New Zealand.
The two shipmates began by noting with sorrow the strong anti-missionary sentiments that they had encountered when the Beagle called at Capetown:
A very short stay at the Cape of Good Hope is sufficient to convince even a passing stranger, that a strong feeling against the Missionaries in South Africa is there very prevalent. From what cause a feeling so much to be lamented has arisen, is probably well known to residents at the Cape. We can only notice the fact: and feel sorrow.
Following a general defense of missionary activity, FitzRoy and Darwin move to specific cases of their own prior observation, particularly to the improved “moral state” of Tahiti:
Quitting opinions…it may be desirable to see what has been doing at Otaheite (now called Tahiti) and at New Zealand, towards reclaiming the ‘barbarians.’…The Beagle passed a part of last November at Otaheite or Tahiti. A more orderly, quiet, inoffensive community I have not seen in any other part of the world. Every one of the Tahitians appeared anxious to oblige, and naturally good tempered and cheerful. They showed great respect for, and a thorough good will towards, the missionaries;…and most deserving of such a feeling did those persons appear to be.
FitzRoy and Darwin were, obviously, attentive to a possible counterargument—that the Tahitians have always been so decent, and that missionary activity had been irrelevant to their good qualities by European taste. The article is largely an argument against this interpretation and a defense for direct and substantial “improvement” by missionaries. Darwin, in particular, presents two arguments, both quoted directly from his journals. First, Tahitian Christianity seems deep and genuine, not “for show” and only in the presence of missionaries. Darwin cites an incident from his travels with native Tahitians into the island’s interior, far from scrutiny. (This incident must have impressed Darwin powerfully, for he told the tale in several letters to family members b
ack home and included an account in his Voyage of the Beagle):
Before we laid ourselves down to sleep, the elder Tahitian fell on his knees, and repeated a long prayer. He seemed to pray as a christian should, with fitting reverence to his God, without ostentatious piety, or fear of ridicule. At daylight, after their morning prayer, my companions prepared an excellent breakfast of bananas and fish. Neither of them would taste food without saying a short grace. Those travellers, who hint that a Tahitian prays only when the eyes of the missionaries are fixed on him, might have profited by similar evidence.
Second, and more important, Tahitian good qualities have been created, or substantially fostered, by missionary activity. They were a dubious lot, Darwin asserts, before Western civilization arrived.
On the whole, it is my opinion that the state of morality and religion in Tahiti is highly creditable…. Human sacrifices,—the bloodiest warfare,—parricide,—and infanticide,—the power of an idolatrous priesthood,—and a system of profligacy unparalleled in the annals of the world,—have been abolished,—and dishonesty, licentiousness, and intemperance have been greatly reduced, by the introduction of Christianity.