Popular Science Monthly/Volume 12/January 1878/Temperaments
By ELY VAN DE WARKER, M. D.
EVERY adult human being carries about with him an atmosphere of individuality. By this means is the gregarious animal called man enabled to preserve in himself such an isolation from the mass of his fellows that he can gain and hold whatever may be his share of prosperity and remembrance. In this individuality lie his powers of offense and defense—the buckler and spear of his ego; and in it also is expressed the sum of his mental and physical traits in such a manner that, once having known, we may remember him. There are two elements that enter into the formation of this distinctive and memorable quality, mental and physical. These factors enter unequally into the formation of this individual total. The element that has really the least to do with that subtile force called character is the one by which we chiefly recognize the man. This is the ensembled physique, the mental picture we have formed of the bodily man; it is only by long association that we come to speak of one by his mental traits, and can recall him to our minds, not by accidents of size, shape, complexion, but by the tone, manner, and quality, of the mental man. It is curious, however, to reflect that our chief means of mutual identity are the same as those by which we distinguish horse from horse, and dog from dog; and that such is the infinite variety in the merely physical development of men, that this is sufficient for the practical affairs of life. In fact, it is not within experience that two human beings ever existed who were so nearly alike that side by side they could not be distinguished. But human individuality is separated from that of the brute by the refinement of a physical quality. This is called temperament. Although temperaments are purely of physical origin, yet their outlet is mainly found in the actions or the mental habits of the individual, and thus it is that temperaments, like charity, cover a multitude of sins. Even those who believe in the immateriality and separate entity of mind, do not hesitate to ascribe the fretfulness, fickleness, temper, and other mental shortcomings of their friends, to faults of temperament. This may in a measure be the result of habit, but I believe that there is about it the force of a truth that even the most spiritual of psychologists cannot escape. It exists as a physical medium, through which the mental life shines forth, tinged and refracted by its passage. The old word expresses it, humors of the body, a mythical, potent, and subtile fluid, mingling with the bodily substance, and rising, exhalation-like, into the brain, obscuring, revealing, exalting, and depressing the operations of the mind according as it is acting well or ill; as hypothetical as the interplanetary ether, yet as real as a fit of the blue devils. This was somewhat the old notion, and a well-fought battle-ground it was, over which the solidists and humoralists contended right gallantly. A standpoint upon a solid basis of fact is to this day wanting from which we may say they were wrong.
Many of these old fathers in medicine fairly reveled in the idea of temperaments. It contained just enough of the mysterious to spur on their wonder-loving minds. All there was of fact about it, however, they brought out, and all that we know about it they knew. We are to this day using their terms and classification, and have added nothing to them. It stands as a fact in physiology which we have inherited from the remotest boundary of historical medicine.
The four qualities of Hippocrates were believed to be the origin of the temperaments. In moisture and dryness, in heat and cold, not as conditions of existence but as entities in life, were found the materials that either singly or together formed the temperaments. They were combined thus: hot and moist produced blood, hence the sanguine temperaments; cold and moist caused phlegm or pituita, and from this the phlegmatic or lymphatic; hot and dry produced yellow bile, and gave us the sanguine or choleric; and cold and dry caused black bile, which predominating in the body resulted in the melancholic or bilious temperament. In order to understand the profound reason involved in this it must be remembered that these four primary principles of living bodies were believed to be compounded of the simple elements of Nature. Here is shadowed, dimly it is true, but from the very depths of Nature, the theory of the correlation of forces, and even evolution itself. Boerhaave was among the first who attempted to improve the classification of Hippocrates, and then followed Hoffmann, Cullen, and Haller, who, however much reason they may have had, failed to refine the rugged simplicity of the old Greek. Absurd as we may deem the incarnation of the four elements in the form of temperaments by Hippocrates to be, yet from the length of time this idea has prevailed, and the profound influence it has exerted upon science for centuries, we may believe that it possessed the soul of truth that exists in things erroneous, as Herbert Spencer says. Not until 1757 was anything like a scientific explanation given. The learned Haller was the first to give the four elements their final overthrow, and place the phenomena upon a physiological basis; and even he failed to suggest any improvement in the old nomenclature. It is strong evidence of the force that exists latently in old ideas that all modern attempts to extend the scope of the Hippocratic terms have never gained credit. Dr. Gregory renamed the temperaments, and added a fifth, which he called the nervous, and which has been accepted and rejected a score of times; while it is a convenient term to use, it is true that it describes no temperament that may not be included under the old terms. Then came Dr. Pritchord, who rejected the reforms of Dr. Gregory, restored the original terms, and barely escaped calling his predecessor hard names. But the temperaments, simple as they may seem, have afforded groundwork for a separate science—not formulated deductions from dry facts, but drawn warm from the mass of living, suffering humanity. Dr. W. B. Powell spent forty years of his life in the study, and at last evolved a "human science" with ten compounds of temperaments with binary, ternary, and quaternary subdivisions. If human science, as taught by Dr. Powell, be true, it ought to be the ceaseless study of every man and woman, taught along with the creed and catechism—which are the spiritual to this its earthly and carnate part—to the youngest child. Lurking in this science are more than Dantesque horrors, which are liable to spring upon the most circumspect of us in the shape of physiological incest; as if in the decalogue and through the ingenuity of man there were not already more crimes than human nature can withstand, that we should be exposed to others we know not of. This physiological crime consists in the marital union of like temperaments. Human science has revealed another latent offense, called sexual incompatibility, which, so far as I know, has not yet, in its sexual guise, obtruded itself in the divorce courts. It is a standing rebuke to those who build imaginary sciences, without a foothold in the solid world of facts, that, in giving their shadowy creations to the people, they are inviting the cold scrutiny of an aggregate common-sense that never fails in time to separate the true from the false.
But temperaments have been made to play a more agreeable rôle in human affairs than in defining physiological crimes. In the history of this physical attribute it is interesting to cite its literary aspects. Ben Jonson devoted whole plays to the idealizations of individual temperaments, in which a peculiarity was made to play its part as a dramatis persona. The keen and careful analysis of the poet in character is immortalized in his play of "Every Man in his Humor." Shakespeare proved himself a good physiologist as well as a good judge of a conspirator in contrasting Cassius, "lean and hungry," with men "that are fat; sleek-headed men, and such as sleep o' nights." In the earlier English novels, temperament was given a more careful study than in the modern school of light literature. Goldsmith proved himself an enemy of the humoral pathologists in saying of Olivia, in "The Vicar of Wakefield," that the temper of woman is generally formed from the cast of her features. Fielding, in his creative novel of "Tom Jones," speaks of temperaments in such a happy vein of his inimitable philosophy, that it is worth quoting and remembering: "I make no manner of doubt," he says, "but that, in this light, we may see the imaginary future chancellor just called to the bar, the archbishop in crape, and the prime-minister at the tail of an opposition, more truly happy than those who are invested with all the power and profit of these respective offices." A more perfect description of a sanguine man was never written. Novelists, as a rule, analyze temperaments the opposite of their own in their ideal characters. Scott generally describes the bilious in his heroes and heroines, and is never purely realistic in describing the sanguine type to which he belonged. Dickens is always happier in his female characters, and they are good specimens of the sanguine. Dolly, the locksmith's daughter, is a very truthful portrait of this type; while Mark Tapley, famous as the character may be, is an atrabilious, who is continually violating his physiology by being happy under the very circumstances that bring out the unmixed misery of his class. Dickens himself was decidedly of the lymphatic—a type he rarely attempted in his creations. Richter, in "Hesperus," gives some very-perfect studies of temperament; but the court physician in that novel is represented of his own type. George Eliot never violates Nature in her female characters, who are generally described as bilious or sanguine; but the least said about her heroes the better. Deronda is surely a mistake. He is first described as a good specimen of the sturdy, bilious man, and is transformed toward the close of the book into the extreme of the sanguine.
To the scientific mind there is always something assuring when we can leave the field of speculation and enter that of fact. Here chemical analysis brings to our aid positive reasons for a classification of men and women according to temperaments. Mr. Rees, quoting from the researches of M. Lecanu, gives us the material for constructing the following table. The figures are ratios to 1,000 parts of blood:
TABLE I. Ratio of Water, Albumen, and Red Blood-Globules in the Blood of Different Temperaments.
This proves conclusively that temperaments have their origin deep and unchangeably fixed in the organic life. Can we, in view of this, look doubtingly upon their potent influence on the current of thought and emotions? Water, plasmic material, and the red blood-globules—the oxygen-carriers of living bodies—rush to the brain in proportions fixed by the law of temperaments; to one brain more, to another less, but with differences sufficient to give vigor, vivacity, tenacity, and mental breadth to the action of one; while the other moves more slowly, its mental life obscured by the smaller proportion of mind-food.
There is one point about which the reader needs to have a clear understanding. This is the difference between temperament and idiosyncrasy. "Temperament is built in a man, as bricks compose a well," says Dr. Southey; "his idiosyncrasy is developed according to the soil in which he is planted, the conditions under which he grows, and the tendency in him to vary." A man has his temperament as a birth-right, his idiosyncrasy he acquires, changes, makes it subject to his will, or is ruled by it. The distinction is broader than this, however. Temperament is a race-attribute. It is distributed like plants according to latitude and altitude. The bilious is tropic; it thrives best near the equator. The lymphatic belongs to the races of the North. Between these polar types are distributed races that monopolize temperaments as they do their language. The Celt is sanguine, the Saxon lymphatic, the Gaul nervous, the Latin bilious. Thus, temperament is pandemic, while idiosyncrasy belongs to the individual. M. Begin calls the first "la variété organique la plus générale," and the latter "celle qui est plus restreinte."
The tendency among recent writers upon physiology is to exclude the bilious, classing it with the nervous, and making three in place of four. This is the classification of M. Michel Lévy. I shall retain the bilious, as being a term too commonly used by learned and unlearned to be omitted from a popular description.
The sanguine temperament presents marked physical traits. The mean height of the male is five feet eight and a half inches, and of the female two and a half inches less. The head is small comparatively, the face is made square by a firm and angular lower jaw, the forehead is slightly sloping, the nose prominent; it has a determined, resolute, exacting look. Under thirty-five the figures of both sexes are sparely covered with fat, but withal muscular. The chest is large, measuring thirty-five inches in average girth, and the abdomen flat. The complexion is light, and is florid only by exception to the rule; the hair light, light brown, or auburn, and often curly. The mouth is usually large, the lower lip full, and the teeth are regular, with a slightly yellow tinge, which indicates firm and lasting dentine. The sanguine are generally good eaters and drinkers. All of the vital functions are active; the large chest-room, the vigorous heart, the firm muscles, insure a bodily activity that keeps the operations of organic life in unconscious and easy motion. Digestion, assimilation, excretion, and elimination, work in harmony and with vigor.
Mentally, this type is the reflection of its physical traits. The rich blood, by its active circulation through the brain, causes vivid and active mental action. The general cast of the mind is never gloomy. The mental vision is outward rather than inward, and sees things near or remote tinted by glowing, joyous colors, as through a prism. This mental outlook never implies profound insight, or deep thought, or conscious indwelling. It is the surface of things that is studied with quick and transient glances of all that is pleasant, revolting from the difficult or painful. The sanguine man, therefore, learns quickly and knows a little of everything, and by his ready tongue and quick wit is good company—a thorough good fellow. He is brave from a sense of perfect muscular strength, loving sport and athletic games. He is quick to anger, but soon forgets wrong; a word and a blow, and oftentimes the blow first, are the features of his wrath.
It is in medicine only that the temperaments have practical importance, if we reject Dr. Powell's new science. Sanguine people are prone to acute diseases of the inflammatory type. Apoplexy, diseases of the heart and blood-vessels, hæmorrhages, acute fevers, pneumonia, pleurisy, and closely-allied disorders, are the forms of disease generally met with. Dr. Southey assigns to this class the old idea of crises; that is, in febrile diseases, at certain times, there will be sudden losses of the fluids of the body spontaneously, by which the diseased action secures a new outlet, and this is followed by a rapid convalescence. These evacuations, if the temperament of the patient be understood, are never interfered with by the physician, as they are Nature's own efforts to throw off the disease. Rapid recovery, or a speedy fatal result, may generally be looked for among sanguine people. In this temperament the physical part of man reaches its most perfect expression; the body is here in even balance with the brain. Such a combination as that of persistent intellectual effort with a typical sanguine temperament is rare. Prof. John Wilson (Christopher North) is an example of this, and of which there is scarce another illustration in literature. This temperament, finding its purer expression in a near approach to human animalism, with soul and body adjusted and evenly poised, a happy mingling of mind and matter, must surely have been the type of the Miltonic man. The fancy cannot paint him other than this, and believe him capable of contending with the dangers, obstacles, and unrelenting hardships, of his life. Of this type have the sailors, colonists, soldiers, and explorers, generally been—all men who lead in the battle with Nature's obstacles.
In the lymphatic temperament we have a direct antithesis of the sanguine. Typically, the lymphatics are heavily framed, the limbs are clumsy and large-jointed, awkward and slow in movement. This is due to the thickness of the articular surfaces of the long bones, and this also explains the large wrists and ankles; the head is large, the face unanimated, thick-lipped, pale, and with large features, the expression listless and apathetic; the eyes are blue or gray, the hair white, blond, or light auburn, and abundant. The male figure is between five feet eight inches and six feet two inches in height, the female five feet six or nine inches high (Southey), and such are the proportions that a person of this temperament rarely meets the artistic ideal of human beauty. The texture of the flesh is soft and flabby, and generally abundant, the muscles small and slow in their development. Puberty is late in its advent; this is but a characteristic, however, of the slow and deliberate manner of the general development. Functions are slowly performed and not evenly balanced; the fluid secretions too abundant, the absorbents inactive in comparison: thus, the figure has the deceptive appearance of a superabundant nutrition. This is a one-sided nutrition, the appropriation of fatty material to the neglect of the solid, motor machinery of brawn and muscles.
The mental traits seem to take direction and tone from the bodily characteristics. The passions move slowly and are easily kept under control, in marked contrast to those of the sanguine man who has no more control than is sufficient to keep him within the not too narrow limits of the social barriers. From the moderate emotional development there is little need of energetic will-power. Where the moral qualities have any chance of growth and exercise they are always "good people," orthodox, and conservative. The mind acts slowly, but is very retentive, logical and sound in its conclusions. They are persistent in their undertakings, honorable in their affairs with other men; commonplace and common-sense govern them in their daily life. They are apt to be dull companions, but constant and steadfast friends.
This temperament is found in its most perfect form among men; women rarely show it uncrossed, especially as it easily blends with other temperaments. There is no doubt but in this type there are inherent defects of histological structure. Dr. Southey says it is due to a too exuberant vegetative cell-life. Whatever may be the radical cause, persons of this type are weak in vital energy, and short-lived. They are the usual subjects of structural changes, such as scrofula, phthisis, and articular rheumatism, and in whom these morbid processes show the largest ratio of mortality. It will be noticed that these are diseases with a marked hereditary force. It would be interesting to study how much of this heredity exists in the morbid processes, or in the temperament itself, which offers a fair field for their onset.
Nature exerts herself in a more eccentric manner in the nervous temperament. Here we find greater variety in the physical signs, and diversity in the mental traits. Typical instances of the nervous temperament are not good specimens anatomically. In stature they are below the average, the bones small and lightly covered with flesh in both sexes up to middle life. The head is large and covered with not over-abundant dark-brown or black hair; the eyes are dark, the skin dark, sallow, and pale; pigmentation of the skin is more abundant than in any other temperament, while the cuticle is hot, dry, and firm. The muscles are small and compact. Persons of this temperament are capable of sudden outlays of great strength, but the muscles do not work in harmony, the movements being oftentimes irregular. The want of nervous coördination is a marked trait, and tells upon their efficiency in any occupation requiring trained and accurate touch. Dr. Southey explains this by what he calls cerebro-central preoccupation, which means that the brain and spinal cord are slow in receiving and responding to the wants of different and remote parts of the body. This is further shown in the unequal distribution of the circulation, the head being often hot while the feet are cold, or the extremities are cold while the body maintains a nearly febrile temperature. The heart beats more rapidly than in other temperaments, or is attended with nervous irregularity in its action. Functionally the nervous temperament is liable to serious complications; the liver is one of the organs more liable to acute derangement—not, however, in the direction of over but rather that of under action. Digestion is a delicate function, the merest trifles interfering with its proper performance. A leading trait of the nervous temperament is the mutual reaction between it and the vital glandular functions; thus sudden mental or nervous impressions will upset the whole glandular machinery, or serious mental or nervous disturbances result from causes acting in the opposite direction.
If we were to select any one quality as the leading trait of the mental constitution of this type, it would be the great emotional tension. The emotions often usurp the place of higher faculties, and reason, judgment, and the sense of right or wrong, are biased or replaced by emotional qualities. They have an acute sense of right or wrong, but they are disposed to give it a personal rather than a vicarious application. They have an extraordinary capacity for both pleasure and misery, and the nervous man may be said to be undergoing one or the other through life, never knowing what it is to be in the happy mean of negation. They are never contented with their surroundings for any great length of time, but chafe and fret against their fate, no matter how happy it may seem. They have great fixity of opinion, and but little respect for that of others; and are prone to find a particular antagonism in persons of their own temperament, The sexual emotions are unduly developed, oftentimes giving tone to the character, or acting with explosive violence. Persons of this type are not among those who form the grand aggregate of the conservative opinion of society, the inflexible and implacable character of which we all know, and which upon the emotional tension of the nervous man often reacts harmfully rather than well. Typical instances of this temperament are confined to the male sex, the other sex usually showing a cross with the sanguine or bilious.
This temperament does not show a liability to any class of disease, but gives its own characteristic reaction upon the disease itself. From the ascendency of the nervous system in the physical and mental composition, diseases of the nerves are very liable to appear, but not as a primary derangement any more than as a complication grafted upon some previously-existing disease. Nervous headache, neuralgia, epilepsy, insomnia, and hysteria, are among the nervous affections most liable to appear, either as primary or secondary derangements. With this class it is difficult to give an opinion as to the result in any serious disease (prognosis), as they often die of diseases that in other temperaments are deemed trifling; and then again, on the contrary, make most surprising recoveries. With them the will-power is oftentimes an element in the recovery, throwing off disease by the determination not to yield to its influence. There is no doubt but that this temperament is more liable to mental derangement than any other; the great emotional intensity and the difficulty of moral control laying the mind open to causes that tend to produce insanity. Many of the nervous constituents of this type belong to the bilious temperament. We have but to tone down the nervous excitability of the first by an addition of the phlegm of the lymphatic, and add flesh to the spare, nervous figure, and we have the bilious temperament. In its typical phase, the subject is apt to be grave, taciturn, even morose; mind and body move slowly but surely, not eccentrically, but by determination and conviction. Persons of this temperament are remarkable for inflexibility of will, sound judgment, strong convictions, abiding affections, and great love for those dependent upon them.
The study of the relations of temperaments to development and vitality is one of great interest. While we know tolerably well their reaction with disease, and the groups of diseases that are liable to cluster round them, we have but few facts bearing upon the normal relations of the temperaments to vital capacity. There are many difficulties in the way of this study. In the first place, we have no unit of measure or comparison, and, in the next, it is difficult to collect the facts. In a very remarkable work consisting mainly of tabulations of a vast number of data relating to anthropometry, or the measurement of men, I discovered facts that throw considerable light upon this subject. During the late war of the rebellion the provost-marshal-general had to pass upon the fitness for military service of a vast number of conscripts. The results of over a million examinations are embodied in two massive quartos, by Dr. J. H. Baxter, late chief medical officer of that bureau of the War Department. From the elaborate statistical table of Dr. Baxter, I am able to construct a few tables that throw light upon some of the more obscure relations of temperaments. The facts embodied in the tables are picked out here and there from this mass of tabulation; while the figures have suffered no manipulation, except such as may be necessary to arrive at mean values.
A word as to the value of complexion as indicating temperament. A light color of the hair and skin, and blue or gray eyes, instead of indicating any one temperament, define broadly a group of two—the sanguine and lymphatic. A sallow or dark complexion, with black eyes and hair, indicates the bilious and nervous, and in this country, among natives, probably an excess of the latter. If, for the sake of narrowing the dark-haired group, we adopt the more modern classification, and ignore the bilious temperament, we have in this class only the nervous, while in the first group we have both the sanguine and lymphatic, with no means of separating them, except that the national characteristic shows an excess of the sanguine over the lymphatic, probably about the ratio of three to one.
TABLE II. Vital Capacity as indicated by Ratio of Chest-Expansion of over Three Inches for all Heights to Complexion. Based upon the examination of 190,621 American-born white men accepted; expressed in ratios of 1,000.
Table II. shows the relation of chest-expansion to complexion. The range of chest-movement, while it cannot be deemed an absolute measure of vitality, which must be regarded rather as the sum of organic and functional action than the degree of perfection in any one set of organs, yet may be fairly assumed to bear a close relation to the general vigor of the system that defines the quality of vital activity. A free chest-expansion implies a large consumption of oxygen, a corresponding degree of force and activity in the. circulation of the blood, and this, in its turn, calls for a large demand for food, with a proportional muscular vigor. In the table, a chest-expansion of over three inches is taken as the basis of comparison, for the reason that, at an expansion less than this, men of impaired strength may be included. It is but necessary to glance at the table in order to understand all that is implied by it—that size and muscular vigor of the sanguine and lymphatic greatly exceed these conditions in the nervous.
TABLE III.—Ratio of Diseases to Complexion.
In Table III. we have the ratio of disease to complexion. In this, the light complexions show their marked predisposition to skin-diseases; and, notwithstanding their free lung-expansion, show a nearly equal liability to diseases of the respiratory organs with those of dark skins. The light men prove their greater glandular and muscular activity by their excess over dark in diseases of the digestive, circulatory, and locomotor systems; while the dark group, although composed largely of men of nervous temperament, nearly equal the light in frequency of nervous disease. It is interesting to note that, in the same table from which Table III. is compiled, Dr. Baxter gives the total of dark men rejected for all diseases at 38,916, and of the light, 83,700, a difference rather less than that indicated by the mean difference as exhibited in our table. In general diseases, which include fevers, infectious diseases, and all others not confined locally, we find the light men leading the dark by a difference only equaled by their excess over the latter in diseases of the digestive system. This is due, I think, in a great measure to the predisposition of the sanguine to diseases of the febrile or inflammatory type, as has been already mentioned.
TABLE IV.—Ratio of Deformities to Complexion.
Table IV. gives an idea of the ratios of deformities in the two groups, and, while not proving much either way, presents a few facts of great interest. It will be observed that the physical defect which shows the greatest difference, and that in favor of the dark class, is deficient size of the chest. In view of the fact that light men exhibit a larger range, of chest-expansion, this excess in the defective size of the chest is unlooked for. The other chest-defect is deformity, in which the difference in ratio in the two groups is only about .18. The fact that two classes are made in the chest-deformities leads me to suppose that the deformities are congenital, or the result of defective development in childhood; while the deficiency in size is the result of disease or injury later in life. This supposition opens the way to an explanation of the phenomenon. Owing to the greater liability of the light, or partly sanguine group, to active inflammations, a potent factor in causing this deficient size of the chest is inflammation, mainly pleurisy and pneumonia, and, as a not uncommon result, a collapse of one, or both, of the chest-walls. This theory is the only one that offers a reasonable explanation of a very remarkable statistical result. The increased ratio in both groups, but notably in the light, of defects or deformities of the feet rather than of the hands, while having no relation to the difference of temperament, shows the careful way in which Nature protects the natural weapons of human beings—the hands. It confirms, in a broad way, what has probably been noticed by the observant reader, that deformities of the lower are more frequent than those of the upper extremities.
These few figures, taken from Dr. Baxter's vast collection of statistics, if not demonstrating anything positively, have at least the merit of not proving too much—a common fault of figures, if we are to believe the anti-statisticians. They are important, however, in showing the direction in which the study of temperaments may be pushed in order to give practical results. Social reformers, so called, human-science men, and less respectable students under various names, have used temperaments as their physiological basis for widely different theories. To one who is content with marriage as established by law, society, and religion, it is a suspicious circumstance that this is the social relation that has sustained the most determined assaults. The physiological attacks have been made in the interests of marriage-reform, "natural marriage," and of no marriage at all. While there is very strong evidence showing that intermarriage between relations tends to the deterioration of the offspring, there are hardly any facts showing that the matrimonial union of healthy persons of like temperaments has the same effect. It is true that social theorists assert the contrary, but they do so without considering that the intermarriage of kin, from which they draw their chief arguments, is surrounded by conditions that cannot exist in the intermarriage of like temperaments. That there are deep-lying physiological reasons against the union of relations, we need go no further than the oft-quoted fact of the sure impairment of the stock of domestic animals from inbreeding, to establish. Whatever the source of this gradual impairment may be, it is wanting in the marriage of those who are allied only by similarity of temperament. In the absence of conditions that are necessary to render the arguments drawn from analogy valid, the advocates of the theory of physiological incompatibility are obliged to fall back upon facts having a direct bearing, and they have in this field, as yet, reaped no harvest. There is, however, in the human family a sort of natural selection existing, that renders a marriage between parties of like temperament not an ordinary occurrence. Both Dr. Ryan and Mr. Walker, in their works on marriage, refer to the common tendency of one sex to seek the opposite temperament in the other. But, upon the subject of matrimony, even in its physiological relations, society unwittingly does very well.