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differences besides that of weight. For instance, I find, from the examination of the brains of three healthy persons, two men and a woman, that the specific gravity of the grey matter in the female brain is inferior to that of the same tissue in the male.
MEDICAL Lady. But the examination of the brains of these three persons does not entitle you to say that the brain substance of the female is structurally and irreparably of an inferior quality to that of the male.
Knight. Certainly not, madam. It entitles neither me nor any one else to say so. I have been careful to avoid saying so, because I do not hold such an opinion. If I did hold it, I would certainly not bring forward such a fact in support of it, because there is good ground for believing that, with regard to the tissue in question, inferior specific gravity means a higher degree of development. The third brain difference to which I wish to direct your attention is one of convolutional arrangement. The brains of women, like their bodies generally, are more symmetrical than those of men, this superior symmetry being due to a comparative poverty in secondary convolutions.
Surgeon (svith an air of triumph). I have now worked out my calculations, and find that they quite overturn your conclusions. l'sing my own measurements, and applying them to your brain weights, I divide the average brain weight in the male by the-let me see-by the average number of inches in stature, and the product gives the average brain weight per inch ; then I go through the same process with the figures belonging to the female sex, and on deducting the one from the other, I find the difference to be so small that it may be neglected as an error of observation. In this way, the alleged superiority of brain weight in the male totally disappears.
Knight (asiae). What a vertiginous statement! (Aloud and sternly.) In kindly undertaking to set me right, sir, you have fallen into blunders which I can only call-egregious. You divide that which is already small by 65), and are so astonished to find it smaller, that you call it an error of observation. It is quite unnecessary to follow you in your abstruse manipulation of the rule of three. I took the average disserence in height to be five inches. You assert that it is only four inches. Agreed. It requires no mathematician to perceive at once that the smaller the average difference in height, the smaller must be the necessary correction in brain weight. If your measurements are correct (though I am at liberty to doubt it, judging from your confusion in handling them) my case is so far the stronger.
PHYSICIAN. In your calculations, it seems to be assumed that every inch of stature should carry with it the same proportionate quantity in brain weight. Analogy shows us that this assumption may be incorrect. For instance, with regard to breathing capacity, it has been found that about three cubic inches go to every inch of stature in the adult, so long as the height does not exceed about 5 feet 4 inches. Above this height, every additional inch of stature carries with it eight additional inches of breathing capacity. On a similar principle, the co-relation between stature and body weight is maintained. Thus, an additional inch in a young man of about an average height carries with it an additional weight of about 5 lbs. But if this held good for the total stature, a man of six feet would weigh 72 inches x 5 lbs. = 360 lbs., or nearly 26 stones. The same principle may apply to the relation between brain weight and bodily stature.
KNIGHT (aside). Ah! here is a masculine intellect at last. (Aloud.) I at once admit the justice of your criticism, sir. I can see clearly that there may be a fallacy in the comparison instituted between brain weight and body height in the sexes. This comparison has been made more to supply an answer to those who have alleged that the sex difference in favour of the male could thus be explained, than with the intention of insisting that these results are of intrinsic importance. My own view is that the absolute excess of brain weight in the male over the female, without reference to stature, is the best criterion which we yet possess of the respective mental energy of the sexes. To proceed : The fourth brain difference has reference to the balance of parts in the male and female brains respectively. The hinder lobes, which are certainly sensory in their functions, are more voluminous in the female than in the male, while the reverse holds true of the middle lobes, which have a motor function.
Lady Doctor (impatiently). We all recognise that there are very great differences between the sexes, and, as women, we are thankful, and indeed frequently rejoice, in being able to do so.
KNIGHT (bowing). The fifth and last difference to which I shall allude is a very momentous one, and relates to blood supply. From observations made during the last four years by a medical friend and myself, we find that the arteries supplying the fore brain are relatively larger in men than in women, while the arteries which supply the hinder brain are relatively larger in women than in men. In other words, the region concerned in volition, cognitions, and ideo-motor processes is most richly flushed with blood in men ; in women, the
same remark applies to the region which is mainly concerned in sensory functions; and thus, with regard to the intellectual and emotional differences between the sexes, anatomical research confirms the teaching of general observation.
MEDICAL LADY, But observations upon such minutiæ as the comparative calibre of arteries will require confirmation before we can adopt conclusions drawn from them.
Knight. I am satisfied that the results of these observations will stand any test that can be applied to them. They have been arrived at after the expenditure of much labour and care, and are corroborated by other results secured by different methods.
LADY DOCTOR. If the forinative influences of life can develop the higher nerve centres, increase the specific gravity of the grey matter, and enlarge the arteries in the case of men, why should not a similar set of influences do as much for women ?
Knight. Your estimate, madam, of the influence of education in determining sexual differences is evidently very high. I am curious to know whether, in your opinion, it also explains the fact that, in the male, the blood is richer in red corpuscles than in the female.
LADY Doctor. As to that, I say nothing. But I do say, that to take the brains of two adults who have been leading widely different lives since six or seven years of age, and to say, “See how different one is from the other ; does it not show that the smaller one should never be treated in the way that has led the larger one to grow ?” seems to me to be bad logic.
KNIGHT. To say so, madam, would be worse than bad logic, for it would qualify the speaker for admission into an asylum as a hopeless, confirmed imbecile. My line of argument, however, is slightly different. It is that these differences which I have described are fundamental, of deep physiological import, and no more the result of education than a woman's mammary glands are, or a man's beard. Further, that to disregard these differences, and to insist on male and female brains working alike, is to incur immediate dangers to health ; that the tendency to disease is particularly strong in the female at the time when womanhood is being approached, and when cducation is being pushed forward with most vigour ; and that functional nervous disorders result at once, and nervous degenerations more remotely, from the attempt to educate girls like boys at this period of life.
LADY Doctor. I think, sir, that instead of conjuring up such terrors, you should try to understand women better, and rid yourself of the habit of being frightened about nothing. You have had
much to do with lunatics. Quiet people, acquainted with what is essentially womanly, refuse to be terrified by such scarecrows.
KNIGHT (a little warmly). Scarecrows, madam! Terrors ! In such terms you describe my predictions as to what will follow the misdirection of education, which, at the same time, you regard as an agent of almost necromantic power. You believe that education can add an ounce to the weight of the brain, modify its structure, alter the balance of its blood supply, and, in short, convert female into male brains, all in the course of one generation ; while you refuse to admit that it can have any influence whatever in causing degenerative changes. Is your view of education, not a little-pardon me, just a little-inconsistent? You hint that my mind has been disturbed by association with lunatics; is it not also possible that your judgment may have been prejudiced by your somewhat exceptional experience of your own sex ?
Lady Doctor. My opinion, sound or unsound, is based upon what I have seen in medical practice as to the general effect of modern changes in educational methods upon the health of women.
OBSTETRICIAN. In so wide a question as that before us, the personal experience of one individual cannot count for very much; my own, however, points to the conclusion that over-pressure in the education of girls is a real, and a very grave danger, frequently followed by serious results. Several cases of nervous break-down in young women, distinctly traceable to this cause, have occurred in my practice during the last few years ; while I have never come across or even heard of an analogous break-down in a boy.
MEDICAL LADY. Is it not a fact, sir, that nature has absolute limitations, and that women can best find out what these are by the experience of life? They will certainly not be prevented from making the experiment by observations upon the brains of lunatics.
KNIGHT (aside). What an admirable example of the female intellect, educated after modern methods. (Aloud.) You combine the Socratic method of interrogation, madam, with a fine, feminine contempt for logic, which, though charming, is not a little perplexing. Although the limitations of nature are absolute, they are also comprehensive, and embrace good and evil, health and disease, idiots and philosophers. To leave women to find out these limitations for themselves by their experience of life is to squander their energy, and to expose them to risk.
MEDICAL LADY. Is it not a fact, sir, that nature, however forced, will always reassert herself, and that the female brain will safely direct the course women will take, and can only take, in life?
KNIGHT (aside). Another fact-and still harping upon naturewhich, no doubt, she spells with a capital N. (Aloud.) If I understand your plea, it is that science and history are to be cast aside, and that we are to give license to every whim and folly that it may enter into the brains of women to conceive. Such a doctrine will find few adherents. Forced nature does reassert herself, as you say; but, alas ! too often in that disordered mind which is a living death.
SURGEON. You have calculated the average brain weight of the sexes from observations made upon the bodies of persons dying at ages ranging from ten to eighty years ; you ought to have confined your observations to adult brain weights for purposes of comparison with adult stature.
Knight. If sex were confined to adults, your objection would have some weight; but I need scarcely remind you, that sex extends to both extremities of life. Practically, my observations were confined to adults, and you would have seen this, had you considered the early age at which maturity as to brain mass is attained, and had you remembered that the mortality in asylums among lunatics under twenty is very small.
SURGEON (shutting up his note-book). I still hold that it is impossible to draw conclusions from a combination of lunatics' brains and sane persons' bodies.
KNIGHT (aside). What nondescript type of brain is this? (Aloud.) From no such extraordinary hotch-potch, sir, have I attempted logical deduction. I used the best materials available. You have still to prove that the stature of lunatics (excluding, of course, idiots and imbeciles) is different from that of sane men and women ; and when you have done so, you will only have strengthened my position.
LADY DOCTOR. With regard to over-pressure, what are the inimediate results to which you have alluded ?
KNIGHT. Perhaps the most common is sleeplessness, a symptom which is often of evil import; but girls not unfrequently suffer from the opposite condition, or a soporific sleep, very deep and difficult to break. In either case, the appetite suffers, solid food is declined or trifled with at breakfast, but the stimulating cup of tea is not refused. At school in the forenoon, such girls find that their power of acquisition is impaired, and that they cannot remember what they have learned ; while to the observer, they look languid, irresolute and drowsy.
LADY Doctor. As for drowsiness, a little drill or gymnastic exercise soon sets that right.
KNIGHT. A much better plan would be to put the girls to bed