Pedagogical Anthropology

by Maria Montessori

No single measurement can express the form; the weight of the body, indeed, may give us a conception of the mass but not of the shape; and the latter, if it needs to be determined in all its limits, requires a series of measurements, mutually related, and signifying the reciprocal connection and harmony of the parts with the whole; in other words, a law. We may establish the following measurements as adapted to determine the form, in other words, as fundamental laws: the total stature, the sitting stature, the total spread of the arms, the circumference of the thorax, and the weight. Of these measures, the two of chief importance are the stature and the weight, because they express the linear index and the volumetric measure of the entire body. The other measurements, on the contrary, analyse this entirety in a sweeping way: thus, the sitting stature, in its relation to the total stature, indicates the reciprocal proportions between the bust and the lower limbs; the perimeter of the chest records the transverse and volumetric development of the bust; and the total spread of the arms denotes a detail that is highly characteristic in the case of man: the development of the upper limbs, which, while they correspond to organs of locomotion in the lower animals, assume in the case of man higher functions, as organs of labour and of mimic speech.

Such measurements constitute a law, because they are in constant mutual relationship, when the normal human organism has reached complete development. The stature, in fact, is equal to the total spread of the arms; the circumference of the thorax is equal to one-half the stature, and the sitting stature is slightly greater than the perimeter of the chest. As regards the weight, it cannot be in direct proportion to any linear measure; nevertheless, an empirical correspondence in figures has been noted that may be recorded solely for the purpose of aiding the memory: the normal adult man usually weighs as many kilograms as there are centimetres in his stature, over and above one metre (for instance, a man whose height is 1.60 metres will weigh 60 kilograms, etc.).

To make these laws easier to understand, we may resort to signs and formulæ. Thus, if we denote the stature by St, the total spread of the arms by Ts, the circumference of the thorax by Ct, the essential or sitting stature by Ss, and the weight by W, we may set down the following formulæ, which will result in practice in more or less obvious approximations:

St = Ts; Ct = St/2; Ct = Ss

And for the weight, the following wholly empirical formula:

W = Kg(St-1 m.).

Stature.—Among all the measurements relating to the form, the principal one is the stature. It has certain characteristics that are essentially human. What we understand by stature is the height of a living animal, when standing on its feet. Let us compare the stature of one of the higher mammals, a dog for instance, with that of man. The stature of the dog is determined essentially by the length of its legs, while the spinal column is supported in a horizontal position by the legs themselves. Such is the attitude of all the higher mammals, including the greater number of monkeys, notwithstanding that these latter are steadily tending to raise their spinal column in an oblique direction, in proportion to the lengthening of their forelimbs, which serve them as a support in walking—a form of locomotion half way between that of quadrupeds and of man. Man alone has permanently acquired an erect position, that renders the bust ( = sum of head and trunk) vertical, and leaves the upper limbs definitely free from any duty connected with locomotion, thus attaining the full measure of the human stature, which is the sum of the bust and the lower limbs. Thus, we may assert that one fundamental difference between man and animals consists in this: that in animals the spinal column does not enter into the computation of stature; while in man, on the contrary, it is included in its entirety. Consequently, in man the stature assumes a characteristic and fundamental importance, because part of it (that part relating to the bust) represents, as a linear index, all the organs of vegetative life and of life in its external relations.

If we examine the human skeleton in an erect position (Fig. 9), it shows us the varying importance of the different parts of its structure, according as they are destined to protect, or simply to sustain. At the top is the skull, an enclosed bony cavity; and this arrangement indicates that it is designed to contain and protect an organ of the highest importance. By means of the occipital foramen, this cavity communicates with the vertebral canal, also rigorously closed, that is formed by the successive juxtaposition of the vertebræ. Such protective formation is in accord with the high physiological significance and the delicate structure of the organs of the central nervous system, which represent the supreme control over physiological life and over the psychic activities of life in its external relations. Below the skull, the structure of the skeleton is profoundly altered; in fact, the framework of the thorax is a sort of bony cage open at the bottom; still, the external arrangement of the bones renders them highly protective to the organs they enclose, namely, the lungs and the heart—physiological centres, whose perpetual motion seems to symbolise the rhythm and consequently the continuity of life.