Here one may ask, perhaps, why it is so desirable that a man should be individuated.  Not only is it desirable, it is absolutely indispensable because, through his contamination with others, he falls into situations and commits actions which bring him into disharmony with himself.  From all states of unconscious contamination and non-differentiation there is begotten a compulsion to be and to act in a way contrary to one’s own nature.  Accordingly a man can neither be at one with himself nor accept responsibility for himself.  He feels himself to be in a degrading, unfree, unethical condition.  But the disharmony with himself is precisely the neurotic and intolerable condition from which he seeks to be delivered, and deliverance from this condition will come only when he can be and act as he feels is confortable with his true self.  People have a feeling for these things, dim and uncertain at first, but growing ever stronger and clearer with progressive development.  When a man can say of his states and actions, ‘As I am, so I act,’ he can be at one with himself even though he struggle against it.  We must recognize that nothing is more difficult to bear with than oneself.  (‘You sought the heaviest burden, and found yourself’ says Nietzsche.)  Yet even this most difficult of achievements becomes possible if we can distinguish ourselves from the unconscious contents.  The introvert discovers these contents in himself, the extravert finds them projected upon human objects.  In both cases the unconscious contents are the cause of blinding illusions which falsify ourselves and our relations to our fellow men, making both unreal.  For these reasons individuation is indispensable for certain people, not only as a therapeutic necessity, but as a high ideal, an idea of the best we can do.  Nor should I omit to remark that it is at the same time the primitive Christian ideal of the Kingdom of Heaven which ‘is within you.’  The idea at the bottom of this ideal is that right action comes from right thinking, and that there is no cure and no improving of the world that does not begin with the individual himself.  To put the matter drastically: the man who is a pauper or parasite will never solve the social question.  2EoAP Para 373

… with the lack of differentiation of the anima and without any relationship to the feminine principle there could be no eros and no relatedness.   TPoPA 231

In the unconscious the inner world and the outer world are not differentiated.  Only that which has become a content of consciousness is described as an inner or an outer phenomenon, that is, either as an introspectively perceived condition, like the welling up of an emotion, or as an “outer” event or object.  Everything else, of which we are not conscious, remains, as before, an undifferentiated part of the occurrences of life.  P&R 19 

for a differentiated personality, or one capable of differentiation, is of the utmost value to the community.  The levelling down of the masses through suppression of the aristocratic or hierarchical structure natural to a community is bound, sooner or later, to lead to disaster.  For, when everything outstanding is levelled down, the signposts are lost, and the longing to be led becomes an urgent necessity.  Human leadership being fallible, the leader himself has always been, and always will be, subject to the great symbolical principles, even as the individual cannot give his life point and meaning unless he puts his ego at the service of a spiritual authority superordinate to man.  The need to do this arises from the fact that the ego never constitutes the whole of a man, but only the conscious part of him.  The unconscious part, of unlimited extent, alone can complete him and make him a real totality.  TDoP 143