PHRENOLOGY (from of,v, mind, and Ahor, discourse) is, in the words of Dr. Spurzheim, the doctrine of the special faculties of the mind, and of the relations between their manifestations and the body, particularly the brain. Without entering upon the question of the nature of the mind, or of the number or nature of its original faculties, it may be admitted as the result of all observation, and a fact on which nearly all physiologists are agreed, that the brain is the part of the body by means of which all the powers or faculties of the mind are manifested. The fundamental principles of phrenology, and those in which it chiefly differs from other psychological systems are, that the manifestation of each of the several faculties of the mind depends on a particular part of the brain, and that, arteris paribus, the degree or strength in which each faculty is manifested in each individual, de pends on the size of its appropriated portion of the brain, or (as it is termed) its organ.
The first principle, that of the plurality of organs in the brain, is supposed to be supported, I, by the analogy of the other compound organs or systems in the body, in which each part has its special func tion ; as, for example, in the digestive system, in which the stomach, liver, and other organs perform each their separate share in the com mon result of digestion of the food ; 2, by the different degrees in which, in different individuals, the several mental functions are mani fested. Even in the earliest period of childhood, and before education can be imagined to have exercised any influence on the mind, children exhibit the most varied dispositions—each presents some predominant propensity, or evinces a singular aptness in some study or pursuit ; and it is a matter of daily observation that every one has his peculiar talent or propensity. But it is difficult to imagine how this could be the case, if the manifestation of each faculty depended on the whole of the brain; different conditions of the whole mass might affect the mind generally, depressing or exalting all its functions in an equal degree, but could not permit one faculty to be strongly and another weakly manifested.
3. The plurality of organs in the brain is supported by the phenomena of some forma of mental derangement. It is not usual for all the mental faculties in an insane person to be equally disordered ; it often happens that the strength of some is increased, while that of others is diminished ; and in many cases one function only of the mind is deranged, while all the rest are performed in a natural manner. 4. The same opinion is supported by the fact that the several mental faculties are developed to their greatest strength at different periods of life, some being exercised with great energy in childhood, others only in adult age ; and that as their energy decreases in old age, there is not a gradual and equal diminution of power in all of them at once, but, on the contrary, a diminution in one or more, while others retain their full strength, or even increase in power. 5. The plurality of cerebral organs appears to be indicated by the phenomena of dreams, in which only a part of the mental faculties are at rest or asleep, while the others are awake, and, it is presumed, are exercised through the medium of the parts of the brain appropriated to them. 6. It is stated that the examination of the brains of individuals, each remarkable for some peculiar propensity or talent, has demonstrated a constant corre spondence in the development of a certain portion of the brain ; and that thus the results of the observations upon which phrenology was first founded by Dr. Gall, exactly coincide with and confirm the argu ments by which its truths may, a priori, be made to seem probable. Lastly, pain has been felt in an organ when the faculty with which it is presumed to be connected has been greatly excited ; and when a faculty has been morbidly manifested during life, disease has sometimes been found to have affected the corresponding part of the brain.