Existential therapist Matthew Bishop, in his blog, quotes philosopher Soren Kierkegaard in reframing Obsessive Compulsive Disorder as an adaptive (yet not necessarily pathological) variation on anxiety:  “This is an adventure that every human being must go through – to learn to be anxious in order that he may not perish either by never having been in anxiety or by succumbing in anxiety. Whoever has learned to be anxious in the right way has learned the ultimate.”