Human civilization tends to increase individual powers of subsistence with relatively small fertility: in other words there is a predominance of ego over sex instincts, or, according to Jung, introversion rather than extroversion. In order to avoid the sacrifice of the race to the individual, nature appears to have supplied man with a stronger sex instinct than required for reproduction. Freud states that the conflict resulting from this is between ego and sex instincts, and Jung believes that it is between introvert and extrovert reactions. There is more in common between the views of Jung and Freud, or the theory of the libido as an essentially psychic force, than the difference in terminology would lead one to expect. Jung does not admit that desexualized primal libido can ever be restored to its original function. Freud and Jung both admit a sexual force capable of sublimation or desexualization, and a force which is innately