Arsenicum Album
One of the largest polycrests, Arsenicum can be used in disorders of virtually every organ system as well as in many serious mental and emotional conditions.  Vithoulkas uses the term, "insecurity" to describe the essence of this remedy, by which he means that the patient has an often overwhelming sense of vulnerability in the world and fear for his well-being and material security.  Starting from his terrible feeling of insecurity, most of the mental symptoms can be readily understood.