The case of the sensualist is somewhat similar to that of the drunkard. Ribot quoting Prosper Lucas, gives the example of a "man cook, of great talent in his calling, has had all his life, and has still at the age of sixty years, a passion for women. To this he adds unnatural crime. One of his natural sons living apart from him does not even know his father, and though not yet quite nineteen, has from his childhood given all the signs of extreme lust, and strange to say, he, like his father, is equally addicted to either sex." (Ribot; Heredity p. 89.) The fact that this son imitated his father's vices at an early age, is not sufficient in itself to assign the cause to heredity. Nor does the fact that he was separated from his father's influence or example, strengthen the assignment beyond dispute. The causes for such conduct are so common that very few men escape from their influence, and whosever does not resist them, falls and becomes a victim. But probably this was a case in which an inherited influence pressed itself so strongly upon him as to become irresistible. What, we ask was inherited? A perverted will? That is absolutely impossible. A perverted will is the outcome of a deliberate choice of evil when the choice of virtue is equally possible. A weakened will, or a will subject to heavy stress is a different thing. There must be some stress upon the will. What is it? It is a well known fact that the exercise of the members of our body results in a great facility of movement being attained. The pianist can, after long practice, execute rapid and complex performances of fingering, which in the early stages of education were absolutely impossible. It is because the nerve centres controlling the muscles employed have been brought to such a high state of activity that they operate almost independently of the will. The nerve centres controlling certain of our functions DO operate independently of the will. Breathing is an example, and although an effort of the will is required to correct bad breathing, yet when once the habit of correct breathing is established, the directing influence of the mind ceases, and the nerve centres discharge their functions automatically.