"That's the thing I want to make clear about depression: It's got nothing at all to do with life. In the course of life, there is sadness and pain and sorrow, all of which, in their right time and season, are normal-unpleasant, but normal. Depression is an altogether different zone because it involves a complete absence: absence of affect, absence of feeling, absence of response, absence of interest. The pain you feel in the course of a major clinical depression is an attempt on nature's part (nature, after all, abhors a vacuum) to fill up the empty space."