Above all it must not be forgotten that the cult of comfort and convenience and what may well be called the habit of luxury in the modern time has greatly increased sensitiveness to pain. There are two elements that enter into suffering, as we have said in the chapter on that subject. The one is the irritation of a sensitive nerve and the other is the reaction to it in the mind of the sufferer. If, for any reason, the nerve has been rendered {273} insensitive, or the mind put in a condition where it cannot receive the irritation, the subject will not feel the pain. If anything has happened to increase the irritability of a nerve, as happens, for instance, when continued irritation has brought more blood to the part than usual and the affected area is hyperemic and swollen, the pain will be greater because the nerve is more sensitive. If anything happens to make the mind more receptive of pain, and especially if the pain message that comes up along a nerve is diffused over a large part of the brain because there is a concentration of attention on it, then too the pain will be ever so much worse. We are, in various ways, adding to this subjective element of pain and therefore increasing it. We are going to need then all the possible consolation that can be afforded by religious motives. In an article written for the _International Clinics_, [Footnote 11] on "Neurotic Discomfort and the Law of Avalanche", I called attention to how much even comparatively mild pains can be increased by concentration of attention. [Footnote 11: Series 23, Vol. IV.] The law of avalanche is a term employed by Ramon y Cajal to indicate the mode by which very simple sensations at the periphery of the body may be multiplied into an avalanche of sensations within the brain. In a lecture of his for _International Clinics_ [Footnote 12] Professor Ramon y Cajal said: "Impressions are made upon single cells at the periphery. As the result of the disturbance of the single cell, an ever-increasing number of cells are affected as the nervous impulse travels toward the nerve-center. Finally the nervous impulses reach the brain and are spread over a considerable group of pyramidal cells in the cortex." [Footnote 12: Series 11, Vol. II.] In his paragraphs on attention he says that if conscious {274} attention is paid to the sensation a great many other cells throughout the brain become affected by it. It may be that every cell which subtends consciousness will at a given moment of intense attention be tingling from a single sensation. If it is unpleasant, the unpleasantness is multiplied to a very serious degree. The "law of avalanche" has a very large place in disturbing the lives of those people who have much time on their hands to think about themselves and who are always solicitous lest some serious condition should be developing.