The object of the present work is to give a brief and plain account of the structure and functions of the body, chiefly with reference to health and disease. This is intended to be introductory to an account of the constitution of the mind, chiefly with reference to the development and direction of its powers. There is a natural connexion between these subjects, and an advantage in studying them in their natural order. Structure must be known before function can be understood: hence the science of physiology is based on that of anatomy. The mind is dependent on the body: hence an acquaintance with the physiology of the body should precede the study of the physiology of the mind. The constitution of the mind must be understood before its powers and affections can be properly developed and directed: hence a knowledge of the physiology of the mind is essential to a sound view of education and morals.

In the execution of the first part of this work, that which relates to the organization of the body, a formidable difficulty presents itself at the outset. The explanation of structure is easy when the part described can be seen. The teacher of anatomy finds no difficulty in communicating to the student a clear and exact knowledge of the structure of an organ; because, by the aid of dissection, he resolves the various complex substances, of which it is built up, into their constituent parts, and demonstrates the relation of these elementary parts to each other. But the case is different with him who attempts to convey a knowledge of the structure of an organ merely by the description of it. The best conceived and executed drawing is a most inadequate substitute for the object itself. It is impossible wholly to remove this difficulty: what can be done, by the aid of plates, to lessen it, is here attempted. A time may come when the objects themselves will be more generally accessible: meanwhile, the description now given of the chief organs of the body may facilitate the study of their structure to those who have an opportunity of examining the organs themselves, and will, it is hoped, enable every reader at once to understand much of their action.

Physical science has become the subject of popular attention, and men of the highest endowments, who have devoted their lives to the cultivation of this department of knowledge, conceive that they can make no better use of the treasures they have accumulated, than that of diffusing them. Of this part of the great field of knowledge, to make "the rough places plain, and the crooked places straight," is deemed a labour second in importance only to that of extending the boundaries of the field itself. But no attempt has hitherto been made to exhibit a clear and comprehensive view of the phenomena of life; the organization upon which those phenomena depend; the physical agents essential to their production, and the laws, as far as they have yet been discovered, according to which those agents act. The consequence is, that people in general, not excepting the educated class, are wholly ignorant of the structure and action of the organs of their own bodies, the circumstances which are conducive to their own health, the agents which ordinarily produce disease, and the means by which the operation of such agents may be avoided or counteracted; and they can hardly be said to possess more information relative to the connexion between the organization of the body and the qualities of the mind, the physical condition and the mental state; the laws which regulate the production, combination, and succession of the trains of pleasurable and painful thought, and the rules deducible from those laws, having for their object such a determination of voluntary human conduct, as may secure the pleasurable and avoid the painful.

Yet nothing would seem a fitter study for man than the nature of man in this sense of the term. A knowledge of the structure and functions of the body is admitted to be indispensable to whoever undertakes, as the business of his profession, to protect those organs from injury, and to restore their action to a sound state when it has become disordered; but surely some knowledge of this kind may be useful to those who have no intention to practise physic, or to perform operations in surgery; may be useful to every human being, to enable him to take a rational care of his health, to make him observant of his own altered sensations, as indications of approaching sickness; to give him the power of communicating intelligibly with his medical adviser respecting the seat and the succession of those signs of disordered function, and to dispose and qualify him to co-operate with his physician in the use of the means employed to avert impending danger, or to remove actual disease.

But if to every human being occasions must continually occur, when knowledge of this kind would be useful, the possession of it seems peculiarly necessary to those who have the exclusive care of infancy, almost the entire care of childhood, a great part of the care of the sick, and whose ignorance, not the less mischievous because its activity is induced by affection, constantly endangers, and often defeats, the best concerted measures of the physician.

The bodily organization and the mental powers of the child depend mainly on the management of the infant; and the intellectual and moral aptitudes and qualities of the man have their origin in the predominant states of sensation, at a period far earlier in the history of the human being than is commonly imagined. The period of infancy is divided by physiologists into two epochs; the first, commencing from birth, extends to the seventh month: the second, commencing from the seventh month, extends to the end of the second year, at which time the period of infancy ceases, and that of childhood begins. The first epoch of infancy is remarkable for the rapidity of the development of the organs of the body: the processes of growth are in extreme activity; the formative predominates over the sentient life, the chief object of the action of the former being to prepare the apparatus of the latter. The second epoch of infancy is remarkable for the development of the perceptive powers. The physical organization of the brain, which still advances with rapidity, is now capable of a greater energy, and a wider range of function. Sensation becomes more exact and varied; the intellectual faculties are in almost constant operation; speech commences, the sign, and, to a certain extent, the cause of the growing strength of the mental powers; the capacity of voluntary locomotion is acquired, while passion, emotion, affection, come into play with such constancy and energy, as to exert over the whole economy of the now irritable and plastic creature a prodigious influence for good or evil. If it be, indeed, possible to make correct moral perception, feeling, and conduct, a part of human nature, as much a part of it as any sensation or propensity—if this be possible for every individual of the human race, without exception, to an extent which would render all more eminently and consistently virtuous than any are at present (and of the possibility of this, the conviction is the strongest in the acutest minds which have studied this subject the most profoundly), preparation for the accomplishment of this object must be commenced at this epoch. But if preparation for this object be really commenced, it implies, on the part of those who engage in the undertaking, some degree of knowledge; knowledge of the physical and mental constitution of the individual to be influenced; knowledge of the mode, in which circumstances must be so modified in adaptation to the nature of the individual being, as to produce upon it, with uniformity and certainty, a given result. The theory of human society, according to its present institutions, supposes that this knowledge is possessed by the mother; and it supposes, further, that this adaptation will actually take place in the domestic circle through her agency. Hence the presumed advantage of having the eye of the mother always upon the child; hence the apprehension of evil so general, I had almost said instinctive, whenever it is proposed to take the infant, for the purpose of systematic physical and mental discipline, from beyond the sphere of maternal influence. But society, which thus presumes that the mother will possess the power and the disposition to do this, what expedients has it devised to endow her with the former, and to secure the formation of the latter? I appeal to every woman whose eye may rest on these pages. I ask of you, what has ever been done for you to enable you to understand the physical and mental constitution of that human nature, the care of which is imposed upon you? In what part of the course of your education was instruction of this kind introduced? Over how large a portion of your education did it extend? Who were your teachers? What have you profited by their lessons? What progress have you made in the acquisition of the requisite information? Were you at this moment to undertake the guidance of a new-born infant to health, knowledge, goodness, and happiness, how would you set about the task? How would you regulate the influence of external agents upon its delicate, tender, and highly-irritable organs, in such a manner as to obtain from them healthful stimulation, and avoid destructive excitement? What natural and moral objects would you select as the best adapted to exercise and develope its opening faculties? What feelings would you check, and what cherish? How would you excite aims; how would you apply motives? How would you avail yourself of pleasure as a final end, or as the means to some further end? And how would you deal with the no less formidable instrument of pain? What is your own physical, intellectual, and moral state, as specially fitting you for this office? What is the measure of your own self-control, without a large portion of which no human being ever yet exerted over the infant mind any considerable influence for good? There is no philosopher, however profound his knowledge, no instructor, however varied and extended his experience, who would not enter upon this task with an apprehension proportioned to his knowledge and experience; but knowledge which men acquire only after years of study, habits which are generated in men only as the result of long-continued discipline, are expected to come to you spontaneously, to be born with you, to require on your part no culture, and to need no sustaining influence.

But, indeed, it is a most inadequate expression of the fact, to say that the communication of the knowledge, and the formation of the habits which are necessary to the due performance of the duties of women, constitute no essential part of their education: the direct tendency of a great part of their education is to produce and foster opinions, feelings, and tastes, which positively disqualify them for the performance of their duties. All would be well if the marriage ceremony, which transforms the girl into the wife, conferred upon the wife the qualities which should be possessed by the mother. But it is rare to find a person capable of the least difficult part of education, namely, that of communicating instruction, even after diligent study, with a direct view to teaching; yet an ordinary girl, brought up in the ordinary mode, in the ordinary domestic circle, is intrusted with the direction and control of the first impressions that are made upon the human being, and the momentous, physical, intellectual, and moral results that arise out of those impressions!

I am sensible of the total inadequacy of any remedy for this evil, short of a modification of our domestic institutions. Mere information, however complete the communication of it, can do little beyond affording a clearer conception of the end in view, and of the means fitted to secure it. Even this little, however, would be something gained; and the hope of contributing, in some degree, to the furtherance of this object, has supplied one of the main motives for undertaking the present work. Meantime, women are the earliest teachers; they must be nurses; they can be neither, without the risk of doing incalculable mischief, unless they have some understanding of the subjects about to be treated of. On these grounds I rest their obligation to study them; and I look upon that notion of delicacy, which would exclude them from knowledge calculated, in an extraordinary degree, to open, exalt, and purify their minds, and to fit them for the performance of their duties, as alike degrading to those to whom it affects to show respect, and debasing to the mind that entertains it.

Though each part of this work will be made as complete in itself as the author is capable of rendering it, and to that extent independent of any other part, yet there will be found to be a strict connexion between the several portions of the whole; and greatly as the topics included in the latter differ from those which form the earlier subjects, the advantage of having studied the former before the latter are entered on, will be felt precisely as the word study can be justly applied to the operation of the mind on such matters.

In the expository portion of the work I have not been anxious to abstain from the employment of technical terms, when a decidedly useful purpose was to be obtained by the introduction of them; but I have been very careful to use no such term without assigning the exact meaning of it. A technical term unexplained is a dark spot on the field of knowledge; explained, it is a clear and steady light.

In order really to understand the states of health and disease, an acquaintance with the nature of organization, and of the vital processes of which it is the seat and the instrument, is indispensable: it is for this reason that the exposition of structure and function, attempted in this first part of the work, is somewhat full; but there cannot be a question that, if it accomplish its object, it will not only enable the account of health and disease in the subsequent part of it to be much more brief, but that it will, at the same time, render that account more intelligible, exact, and practical.

S. S.

THE
PHILOSOPHY OF HEALTH.