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Measure of Heads
Transcript of Measure of Heads
-Galton, a pioneer of modern statistics.-Galton coined the term "eugenics" in 1883.
-Quantification was Galton's god.
-Galton's major work on the inheritance of intelligence ( Hereditary Genius, 1869) included anthropometry among its criteria, but his interest in measuring skulls and bodies peaked later when he established a laboratory at the International Exposition of 1884. There, for threepence, people moved through his assembly line of tests and measures, and received his assessment at the end. A Curtain-Raiser with a Moral: Numbers Do Not Guarantee Truth -In 1906, a Virginia physician, Robert Bennett Bean, published a long, technical article comparing the brains of American blacks and whites.
-Bean took special pride in his data on the corpus callosum, a structure within the brain that contains fibers connecting the right and left hemispheres.
-Bean reasoned that he might rank races by the relative sizes of parts within the corpus callosum. So he measured the length of the genu, the front part of the corpus callosum, and compared it with the length of the splenium, the back part.
-He plotted genu vs. splenium and obtained, for a respectably large sample, virtually complete separation between black and white brains.
-Franklin P. Mall, Bean's mentor at Johns Hopkins, became suspicious: Bean's data were too good. He repeated Bean's work, but with an important difference in procedure—he made sure that he did not know which brains were from blacks and which from whites until after he had measured them. For a sample of 106 brains, using Bean's method of measurement, he found no difference between whites and blacks in the relative sizes of genu and splenium. Major contentions of this chapter and book: 1. Scientific racists and sexists often confine their label of inferiority to a single disadvantaged group; but race, sex, and class go together, and each acts as a surrogate for the others.
2. Prior prejudice, not copious numerical documentation, dictates conclusions.
3. Numbers and graphs do not gain authority from increasing precision of measurement, sample size, or complexity in manipulation. Basic experimental designs may be flawed.
4. Craniometry was not just a plaything of academicians, a subject confined to technical journals. Conclusions flooded the popular press. Masters of craniometry: Paul Broca and His School -Paul Broca (1824-1880), professor of clinical surgery in the faculty of medicine, had founded the Anthropological Society of Paris in 1859.
-Broca stated “In general, the brain is larger in mature adults than in the elderly, in men than in women, in eminent men than in men of mediocre talent, in superior races than in inferior races ( 1861, p. 304). . . . Other things equal, there is a remarkable relationship between the development of intelligence and the volume of the brain (p. 188).
Conclusions came first and Broca's conclusions were the shared assumptions of most successful white males during his time—themselves on top by the good fortune of nature, and women, blacks, and poor people below. -His facts were reliable, but they were gathered selectively and then manipulated unconsciously in the service of prior conclusions. Selecting Characters -When the "Hottentot Venus" died in Paris, it was discovered she had the largest brain of France. Small-Brained Men of Eminence Large Brained Criminals -The large size of many criminal brains was a constant source of bother to craniometricians and criminal anthropologists. Broca tended to dismiss it with his claim that sudden death by execution precluded the diminution that long bouts of disease produced in many honest men. In addition, death by hanging tended to engorge the brain and lead to spuriously high weights. Flaws in a Pattern of Increase Over Time Of all Broca's studies, with the exception of his work on differences between men and women, none won more respect or attention than his supposed demonstration of steady increase in brain size as European civilization advanced from medieval to modern times (Broca, 1862b).
-Broca obtained large samples from each of three Parisian cemeteries, from the twelfth, the eighteenth, and the nineteenth centuries. Their average cranial capacities were, respectively, 1,426, 1,409, and 1,462 cc
-Broca's division of the nineteenth-century sample by social class also brought trouble as well as relief—for he now had two samples from common graves and the earlier one had a larger mean capacity, 1,409 for the eighteenth century vs. 1,403 for the nineteenth. But Broca was not to be defeated; he argued that the eighteenth-century common grave included a better class of people. In these pre-revolutionary times, a man had to be really rich or noble to rest in a churchyard. The dregs of the poor measured 1,403 in the nineteenth century; the dregs leavened by good stock yielded about the same value one hundred years before. -The small brains were troublesome, but Broca, undaunted, managed to account for all of them. Their possessors either died very old, were very short and slightly built, or had suffered poor preservation. Front and Back -Broca often used the distinction of front and back, particularly to extract himself from uncomfortable situations imposed by his data.
-He often unleashed the double whammy against inferior groups—small size and posterior prominence: "Negroes, and especially Hottentots, have a simpler brain than ours, and the relative poverty of their convolutions can be found primarily on their frontal lobes"
-The argument of front and back,* so flexible and far-ranging, served as a powerful tool for rationalizing prejudice in the face of apparently contradictory fact. Consider the following two examples. The Cranial Index -Beyond brain size itself, the two misused measures of craniometry were surely the facial angle (jutting forward of face and jaws—the less the better), and the cranial index.
-As for blacks, they had acquired both a posterior elongation and a diminution in frontal width, thus giving them both a smaller brain in general and a longheadedness. Womens Brains -Of all his comparisons between groups, Broca collected most information on the brains of women vs. men. Broca centered his argument about the biological status of modern women upon two sets of data: the larger brains of men in modern societies and a supposed widening through time of the disparity in size between male and female brains.
-He based his most extensive study upon autopsies he performed in four Parisian hospitals.
-Maria Montessori did not confine her activities to educational reform for young children. She lectured on anthropology for several years at the University of Rome and wrote an influential book entitled Pedagogical Anthropology (English edition, 1913). She was, to say the least, no egalitarian. She supported most of Broca's work and the theory of innate criminality proposed by her compatriot Cesare Lombroso. She measured the circumference of children's heads in her schools and inferred that the best prospects had bigger brains. But she had no use for Broca's conclusions about women. In 1879 Gustave Le Bon, chief misogynist of Broca's school, used these data to publish what must be the most vicious attack upon women in modern scientific literature.
"In the most intelligent races, as among the Parisians, there are a large number of women whose brains are closer in size to those of gorillas than to the most developed male brains. This inferiority is so obvious that no one can contest it for a moment; only its degree is worth discussion. All psychologists who have studied the intelligence of women, as well as poets and novelists, recognize today that they represent the most inferior forms of human evolution and that they are closer to children and savages than to an adult, civilized man. They excel in fickleness, inconstancy, absence of thought and logic, and incapacity to reason. Without doubt there exist some distinguished women, very superior to the average man, but they are as exceptional as the birth of any monstrosity, as, for example, of a gorilla with two heads; consequently, we may neglect them entirely ( 1879, pp. 60- 61)." Postscript -Craniometric arguments lost much of their luster in our century, as determinists switched their allegiance to intelligence testing—a more "direct" path to the same invalid goal of ranking groups by mental worth—and as scientists exposed the prejudiced nonsense that dominated most literature on form and size of the head.-After all, what can be simpler than weighing a brain?
—Take it out, and put it on the scale. One set of difficulties refers to problems of measurement itself: at what level is the brain severed from the spinal cord; how much time elapsed after death; was the brain preserved in any fluid before weighing and, if so, for how long; at what temperature was the brain preserved after death. Most literature does not specify these factors adequately, and studies made by different scientists usually cannot be compared. Context -A unbeatable argument. Deny it at one end where conclusions are uncongenial; affirm it by the same criterion at the other. Broca did not fudge numbers; he merely selected among them or interpreted his way around them to favored conclusions. -Broca claimed “But this does not destroy the value of small brain size as a mark of inferiority. The table shows that West African blacks have a cranial capacity about 100 cc less than that of European races. To this figure, we may add the following: Caffirs, Nubians, Tasmanians, Hottentots, Australians. These examples are sufficient to prove that if the volume of the brain does not play a decisive role in the intellectual ranking of races, it nevertheless has a very real importance” (1873a, p. 38). Sarah "Saartjie" Baartman (before 1790 – 1815) was the most famous of at least two Khoikhoi women who were exhibited as freak show attractions in 19th-century Europe under the name Hottentot Venus—"Hottentot" as the then-current name for the Khoi people, now considered an offensive term and "Venus" in reference to the Roman goddess of love. Study: Stephen Jay Gould, Crusader Against Scientific Bias, Was Guilty of It Gould, who died in 2002 was a colorful figure in biology, but among some scientists, he had a reputation for muddling the facts as well as a tendency to polemicize Scientists’ responses have shown disappointment in Gould http://www.wired.com/wiredscience/2011/06/gould-morton-revisited/ This isn’t the first time that scientists have looked into Gould’s assertion and found it lacking, writes the NYTimes.
http://www.nytimes.com/2011/06/14/science/14skull.html?_r=2&partner=rss&emc=rss Chapter 3
Measure Heads Stephen Jay Gould was an American paleontologist, evolutionary biologist, and historian of science. He was also one of the most influential and widely read writers of popular science of his generation