Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER II THE CHARACTERISTICS OF ORIGINAL NATURE DEPENDENCE ON PHYSIOLOGICAL STRUCTURE. — The inheritance of an individual, whether it be that of family, sex, or race, is in terms of physiological struc- what i$ the ture, not in terms of mental states. A baby is not phys'cal heir to any ideas, his emotions or ideals are not ready- mental made, he does not inherit consciousness as such; he does inherit a complicated system of neurones acting and developing according to certain laws of growth. The various theories as to the interaction of brain and mind, happenings in the synapses and states of consciousness need not be entered upon here. For our purpose it is enough to state that any individual's original nature is related in some very close way to the action of his nervous system. A child acts as a human being rather than as an animal because he inherits a human nervous system ; he is interested more in things than in people, is pugnacious and matter-of-fact because he inherits the nervous system of a male ; he is a musician rather than a business man because he inherits the nervous system of a Bach. No matter how general the trait may be, no matter how minute and unimportant the characteristic, its presence is dependent on some connection of the neurones. It is not necessary here to go into a detailed description of the physiology of the brain and spinal cord. It is perhaps sufficient to recall a few important facts from general psychology. The nervous system is composed of neurones of three types : those that receive, the afferent ; those that effect action, the efferent; and those that connect, the associative.The meeting places of these neurones are the synapses. All neurones have the three characteristics of sensitivity, conductivity, and modifiability. In order...