Theories of Race

Paul Broca

  • Paul Broca's portrait

    Paul Broca



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A distinguished clinical surgeon and anatomist now known primarily for his discovery of “Broca’s gyrus,” an area of the brain which, when diseased or impaired, results in loss of speech, Paul Broca was fascinated by the rapid emergence of the naturalistic study of man, and by Samuel George Morton’s craniology in particular. When not performing surgery, Broca was developing new instruments for measuring skulls. (See illustrations below.) He became convinced that intelligence was linked to brain size and that the various races exhibited a wide range of physical characteristics that explained differences of other kinds.

These differences, he believed, could best be measured and assessed by systematic research conducted in the laboratory rather than by observation in the field; he believed, too, that such research should be conducted under the name of anthropology, or the study of the physical as opposed to the cultural or other characteristics of man. In 1859, nine years after the collapse of the Ethnological Society of Paris and four years before the founding of the Anthropological Society of London by Richard Francis Burton and James Hunt, Broca founded the Société d’Anthropologie de Paris, the first such society in the world. He then founded the first professional journal of anthropology and the first academic unit with that name.

Although Broca’s is one of only seventy-two names inscribed on the Eiffel Tower, his work in anthropology was controversial at the time and has become moreso in the years since. He argued that just as mature adult men have larger brains than the elderly, women, and children, eminent men have the same advantage over “men of mediocre talent.” He extended the implications of this discovery to races, ranking Anglo-Saxons as “humanity’s first race” and Australians and Tasmanians as the last, clearly inferior in every way. He attacked those who questioned these premises for permitting their social goals or moral principles to dominate their commitment to empirical truth.

In The Mismeasure of Man Stephen Jay Gould rehearses the history of Broca’s experiments and disputes, and concludes that it was Broca who permitted his principles to overrule the evidence. “One cannot read Broca without gaining enormous respect for his care in generating data,” Gould wrote; but at the same time, he added, it was clear that Broca’s facts were “gathered selectively and then manipulated unconsciously in the service of prior conclusions” (117).* These prior conclusions included the convictions that “human races could be ranked in a linear scale of mental worth,” and that the position of races relative to each other could be scientifically determined. All in all, Gould says, Broca’s work represents “the best case of hope dictating conclusion that I have ever encountered” (127).

Under Broca’s uncompromising leadership, French anthropology took a particular interest in the subject of race, a subject far removed from the field of anatomy in which Broca had gained his reputation. Broca threw himself into the work, becoming persuaded through assiduous labors in the laboratory, including extensive skull-measuring, that while races appeared to be biologically distinct from each other, some cross-racial hybrids, as between Saxons and Celts, were highly fertile even if others, as between Europeans and Hottentots, had limited or diminishing fertility, probably due to the zoological distance between them. This discovery, with its suggestion that racial distinctions might also be species distinctions, was the basis for his thinking about race.

As Broca admitted in a seventy-page essay he clearly intended to be a major contribution to the discourse on race, “On the Phenomenon of Hybridity in the Genus Homo” (1864), his thinking was equivocal and suggestive, in large part because neither race nor species had satisfactory fixed definitions. Many polygenists or “pentagenists” (believing in five races) had, he said, been beguiled into error by “the ambiguous term race” and the equally ambiguous term species, terms that seemed to suggest different concepts when in fact neither was clear. Indeed, Broca does not seem committed to the concepts of race or species at all. “Every confusion in words,” Broca said, “exposes us to errors in the interpretation of facts”; and yet he was capable of using both terms as if they were interchangeable, speaking, for example, of “different degrees of homœogenesis, according to the races or species.”

Taking a certain distance from all prevailing theories of race, which he thought to be based on mere abstractions useful to the scientist rather than facts grounded in reality, Broca nevertheless supported the notion that there might be “natural groups” that could be considered “fundamental” or “principal” and that these had given rise to “secondary” groups. The evidence from fertility studies supported, he believed, the conclusion that the primary or natural groups were more biologically distinct than the secondary groups. The fundamental groups were, by this test, more like species than like races while the reverse was true for the secondary groups. Broca thought this a decisive intervention, one that disproved both the monogenists like Prichard, who thought that all races were uniformly prolific, and the polygenists such as Gobineau, Knox, and Nott who held that racial crossing was invariably degenerative. His essay was considered so significant that the London Anthropological Society sponsored an immediate translation, the source of the passages quoted below.

The first passage, in which he lays out his premises, is from the beginning of the essay. The second passage is from the end, where, Broca addresses possible political implications of his argument. Sensitive to the fact that his partially or equivocally polygenist arguments could be enlisted in support of slavery, Broca pointed out that many clergymen in the American South were both Biblical monogenists and fervent believers in natural inequalities and the divine justice of slavery. This was, he argued, a point in favor of polygenesis, for only on this basis was it possible to object to slavery on moral grounds.

Although Broca is today often associated with racist science, he is among other things largely responsible for creating the biological category of the human hybrid, which contributed to the legitimation of racial mixing (see Ashok in Further Reading).

*Stephen Jay Gould, The Mismeasure of Man (New York:  Norton, 1996).

“On the Phenomenon of Hybridity in the Genus Homo


Section I. General Observations on Crossing in Human Races

Among the various characters which distinguish the numerous varieties of the genus homo, some are more or less important, and more or less evident. To distinguish two races, a single character, however slight, is sufficient, provided it be hereditary and sufficiently fixed. If, for instance, two peoples differed merely from each other by the colour of the hair and the beard, though they may resemble each other in every other respect, by the simple fact that the one has black, whilst the other has fair hair, it may be asserted that they are not of the same race. This is the popular and the true meaning of the term race, which, however, does not necessarily implicate the idea either of identity or diversity of origin. Thus all ethnologists and historians, all the monogenists, and polygenistic authors say that the Irish proper are not of the same race as the English. The Germans, the Celts, the Basques, the Sclaves, the Jews, Arabs, Kabyles, etc., etc., are considered more or less separate races, more or less easy to be characterised, and more or less distinguished by their manners, tongues, history and origin. There are thus a large number of human races; but if, instead of considering all the characters, we confine ourselves to take into consideration but a few of the more important, or if, after having by an analytical process, first studied the various races separately, we now subject them to a synthetic process, we soon recognise that there exists among them numerous affinities, which enable us to dispose them in a certain number of natural groups.

The ensemble of the characters common to each group, constitute the type of that group. Thus, all the races we have just enumerated, and many others, have the skin white, regular features, soft hair, oval face, vertical jaws, and elliptical cranium, etc. These points of resemblance give them in some sort a family likeness, by which they are recognised at once, and which has caused them to be designated by the collective name of Caucasian races. The hyperborean races, and those of Eastern Asia, constitute the family of Mongolian races; the group of Ethiopian races equally comprises a large number of black races with woolly hair, and a prognathous head. The American and the Malayo-Polynesian races form the two last groups.

It must not be believed that all human races can with equal facility be ranged in either of these divisions; nor must we believe that the characteristic traits of one group are equally marked in all the dependent races; nor even that they are found combined in any of these races; nor, finally, that in the centre of each group we find a typical race in which all the characters have their maximum of development. This might be the case if all known races had descended from five primitive stocks, as admitted by several polygenists, or if, as many monogenists think, humanity, one in the beginning, had soon afterwards been divided into five principal trunks, from which issued, as so many accessory branches, the numerous sub-divisions which constitute the secondary races. But there is no race which can pretend to personify within itself the type to which it belongs. This type is fictitious; the description is an ideal one, like the forms of the Apollo de Belvedere. Human types, like all other types, are merely abstractions, and in proportion as we attach more importance to this or that character, we obtain a more or less considerable number of types. Thus, Blumenbach had five, Cuvier only three, and Bérard describes fifteen types. This is also proved by the fact, that whilst many races attach themselves directly and evidently to a fixed type, there are others belonging to two very dissimilar types. Thus the Abyssinians are Caucasian in form and Ethiopian by colour. The description of the principal types is thus merely a methodical process, fit to facilitate, by the formation of a certain number of groups, the comparison of human races, and to simplify the partial description of each. This division has, moreover, the advantage of establishing for the greater part of the races, their degree of relative affinity or divergence. It even accords to a certain point with their primitive repartition upon the surface of the globe, which has permitted, without doing any violence to the facts, to distinguish the types by denominations borrowed from geography.

There is in the human mind a tendency to personify abstractions. These ideal types have usurped a place in the domain of facts, so that a real existence has been given to them. The monogenists had, strictly speaking, a right to do so without any violence to their principles; but the polygenists, who have followed their example, have sinned against logic. The former attribute all varieties of the human species to the numerous modifications of five principal races, issued themselves from one common stock, and the same influences which, according to then, have in the origin produced fundamental races, have afterwards by an analogous process produced the secondary races. All this is sufficiently clear; and such stood the question when 10the polygenists appeared in the arena. Their first efforts were directed to attack the doctrine in its essential foundations, and to demonstrate that by no natural causation could Whites be transformed into Negroes, or Negroes into Mongolians; they therefore proclaimed the multiplicity of human origin and the plurality of species. Be it that they have shrunk from the idea of causing too great a revolution in science, or that they thought that it would conduce sooner to the triumph of their doctrine, they retained as far as possible the number of species, and confined themselves to assume a primitive stock for each of the five races described by the Unitarians. I do not assert that all polygenists followed this course, as some proceeded in a more independent manner. Bory de Saint-Vincent, Desmoulins, P. Bérard, Morton, had the courage to break entirely with the past, and to remodel the classical divisions. They found, however, but few imitators; and many polygenists are to this day content to assign a distinct origin to each of the five principal trunks, which constitute for the monogenists the five fundamental races, but which are to us only natural groups formed by the union of races or species of the same type. They continue also very often to use the term race to designate the ensemble of all individuals of each group, adopting thus by a sort of transaction the language of those whose system they reject; and thus they speak of the white or Caucasian race, the yellow or Mongolian race, the black or Ethiopian race, etc., as if all these individuals of a Caucasian type resembled each other to constitute one race; as if, for instance, the brown Celts and the fair-haired Germans had descended from the same primitive stock. This contradiction has given a handle to the monogenists; for if climate and mode of life may cause a German to become a Celt, there is no reason why, under certain influences, a Celt might not become a Berber, a Berber a Foulah, a Foulah a Negro, and a Negro an Australian.

I easily comprehend how careful we ought to be to employ in Anthropology the term species. It can scarcely be used with certainty until science has clearly circumscribed the limits of each species of men. This moment is not come yet, and may, perhaps, never arrive, for, in the midst of constant changes11 produced by crossing, migrations, and conquests, and with the certainty that several races, or a great number of them, have disappeared within historical time, it seems impossible to appreciate the degree of purity of certain races, to discover their origin, to know whether they are autochthonic or exotic, whether they belonged originally to this or that Fauna, and re-establish the Ethnology of our planet as it was in the beginning. To fix the number of primitive species of men, or even the number of actual species, is an insoluble problem to us, and probably to our successors. The attempts of Desmoulins et Bory de Saint Vincent have only produced imperfect sketches, which have led to contradictory classifications, where the number of arbitrary divisions is nearly equal to more natural divisions.

The term species has, in classical language, an absolute sense, implying both the idea of a special conformation and special origin, and if some races—the Australians, for instance—unite these conditions in a sufficient degree, to constitute a clearly marked species, many other pure or mixed races escape, in this respect, a rigorous appreciation. It is for these reasons that many polygenists, after having proclaimed the multiplicity of the origins of humanity, and having recognised the impossibility of determining the number and the characters of the primitive stocks, have justly avoided methodically to divide the human genus into species. Many among them, however, who thought that they were, nevertheless, bound to establish divisions, have committed the error to accept the basis of the classification of the monogenists, and, like them, to establish five chief human families, and, like them, to admit that the individuals of each family are issued from a common trunk, with this difference, that, whilst the monogenists assume that the five primary trunks have proceeded from the same stock, and have the same roots, the pentagenists (if we may use this term) assume five distinct and independent stocks. Logically speaking, it would have been requisite to term the five fundamental races of the monogenists species, but it is easy to perceive that, for many reasons, the term species cannot be employed here in an absolute sense. The pentagenists have felt this, and, for want of a better term, use the word race, which has thus been diverted from its real acceptation. . . . The word race has thus, in the language of authors, two very different significations; one is particular and exact, the other general and misleading. Taken in the first sense, it designates individuals sufficiently resembling each other, that we may, without prejudging their origin, and without deciding whether they are the issues of one or several primitive couples, admit, if necessary, as theoretically possible, that they have descended from common parents. Such are, for instance, among the white races, the Arabs, the Basques, the Celts, the Kimris, the Germans, the Berbers, etc.; and among the black races, the Ethiopian Negroes, the Caffres, the Tasmanians, Australians, Papuans, etc.

In the second, that is to say, in a general sense, the term race designates the ensemble of all such individuals who have a certain number of characters in common, and who, though differing in other characters, and divided, perhaps, in an indefinite number of natural groups or races, have to each other a greater morphological affinity than they have with the rest of mankind.

Every confusion in words exposes us to errors in the interpretation of facts . . . . (7-13)

If all men are descendants of one couple,—if the inequality of races has been the result of a cure more or less merited,—or again, if the one have degraded themselves, and have allowed the torch of their primitive intelligence to become extinct, whilst the other have carefully guarded the precious gift of the Creator,—in other words, if there be cursed and blessed races,—races which have obeyed the voice of nature and races which have disobeyed it,—then the Rev. John Bachmann is right to say that slavery is a divine right; that it is a providential punishment; and that it is just, to a certain point, that those races who have degraded themselves should be placed under the protection of others . . . . But if the Ethiopian is king of Soudan by the same right as the Caucasian is king of Europe, what right has he to impose laws upon the former, unless by the right of might? In the first case, slavery presents itself with a certain appearance of legitimacy which might render it excusable in the eyes of certain theoreticians; in the second case, it is a fact of pure violence, protested against by all who derive no benefit from it.

From another point of view, it might be said that the polygenist doctrine assigns to the inferior races of humanity a more honourable place than in the opposite doctrine. To be inferior to another man either in intelligence, vigour, or beauty, is not a humiliating condition. On the contrary, one might be ashamed to have undergone a physical or moral degradation, to have descended the scale of beings, and to have lost rank in creation. (70-71)

The Stereograph of Broca
illustration of median facial goniometer
Median facial goniometer of M. Broca, in position for taking the facial angle of Jacquart, whose apex is at the sub-nasal point. The two auricular pins, 0, being in place, the point A being on the superior alveolar point, and the branch K B being placed in its proper position the instrument also gives the angle of Cloquet. N. (95)

Both illustrations from Paul Topinard, Anthropology, with preface by Paul Broca, trans. Robert T. H. Bartley (London: Chapman and Hall, 1878), 268, 330.

Samantha Sharon Ashok, “The History of Race in Anthropology:  Paul Broca and the Question of Human Hybridity,” at:

Ian Hacking, “Making up People,” London Review of Books 28 (2006) 16: 23-26.