These are excerpts from an essay Edward C. Whitmont wrote for Meeting the Shadow called "The Evolution of the Shadow." They're as great as ever, in fact, they get more pertinent all the time, so I'm bringing them to light again today.
The book I'm taking them from, Meeting the Shadow, The Hidden Power of the Dark Side of Human Nature, should definitely be in your library. It's a collection of 65 different essays on the shadow. Edited by Connie Zweig & Jeremiah Abrams, A New Consciousness Reader, St. Martin's Press, Jeremy Tarcher, 1991.
"The term shadow refers to that part of the personality which has been repressed for the sake of the ego ideal. Since everything unconscious is projected, we encounter the shadow in projection — in our view of "the other fellow."
…Where a shadow projection occurs we are not able to differentiate between the actuality of the other person and our own complexes. We cannot tell fact from fancy. We cannot see where we begin and he ends. We cannot see him; neither can we see ourselves.
…Ask someone to give a description of the personality type which he finds most despicable, most unbearable and hateful, most impossible to get along with, and he will produce a description of his own repressed characteristics… the qualities are so unacceptable to him precisely because they represent his own repressed side; only that which we cannot accept within ourselves do we find impossible to live with in others… negative qualities which we find relatively easy to forgive are not likely to pertain to our shadow.
…The shadow is the archetypal urge for a scapegoat, for someone to blame and attack in order to vindicate oneself and be justified; it is the archetypal experience of the enemy… to the extent that I have to be right and good, he, she, or they become the carriers of all the evil which I fail to acknowledge within myself…"