3. As for the third assumption of phrenology, namely, that brain development is reflected in the cranial size or protuberances, it should be sufficient to point out that even if this were so it would be meaningless for our purpose, since we are compelled to abandon the belief in a relation between mass of tissue and even the simplest sensory or motor capacity. But such further disproof as may be required is readily furnished by an actual attempt to remove from their cranial boxes the brains of various animals, and by noting that the shape and thickness of the bones gives little indication as to whether brain tissue, cerebrospinal fluid, or supporting tissues are to be found underneath a given protuberance or depression.
4. The fourth assumption of phrenology, that sparse and casual observation of striking cases is sufficient ground for generalization, we should be able to dismiss at once as utterly inadequate and miscalculated. It is impossible to find consistent recorded instances in which groups of individuals, selected at random, with definitely determined and measured mental or moral characteristics, have been shown to confirm, by their cranial geography, even the most elementary doctrines of that phrenology which still offers to diagnose the individual's psychic constitution and to commend to his future consideration the vocation of engineering, publishing, or preaching, as the case may be. Practicing phrenologists have repeatedly been invited to submit one bit of objective evidence for their pretensions, or to submit themselves to tests under controlled conditions. The invitations are refused, and the inquirer is referred instead to the dogma of some foreign and deceased authority. Such investigations as have been recorded have resulted in negative conclusions, or in contradictory data, or in coefficients with such high probable errors as to make the figures unreliable.
Very often practicing phrenologists and phrenological vocational experts seek to justify their operations and pretensions by pointing out that they do not rely solely on the cranial geography, but more often on other characteristics of the individual's body, such as the concavity or convexity of his profile, the shape of his jaw, the texture of his skin, the shape of his hands, the color of his hair and eyes, the proportions of his trunk, etc. Contemporary vocational counsellors who have enjoyed considerable vogue and commercial repute are especially given to citing these criteria; several recently published tables of these clues are available. Historically, the attempts to formulate principles of physiognomy antedate phrenology by many centuries. Logically, however, physiognomy follows phrenology, as a transition from the formulation of structure to the formulation of behavior. There is a very widespread belief that many mental and moral characteristics betray themselves in special facial items. The shifting eye, lofty brow, massive jaw, thin lips, large ear, protruding or receding chin, dimple, wrinkle, tilted nose, thin skin, prominent veins, and many other characteristics have come, in fiction and in table-talk, to symbolize specific characteristics. The same thing is true of the shuffling gait, the erect body, the protruding paunch, the curved shoulders, enlarged knuckles, stubby or elongated fingers, the short neck, the long arm, and the manner and rate of stride. It is but a step from these to the signs afforded by clothing, its selection, care, and mode of wearing.