We cannot help recognizing the close agreement of physical and spiritual crises; this, again, demonstrates the continuity and exact correspondence of Natural Law on the different planes of being. [The Law of Hermes: ~As above, so below; as in the inner, so in the outer; as in the lesser, so in the greater.~] We of the Nature Cure school know that this great Law of Crises dominates the cure of chronic disease. Every case is another verification of it; in fact, every decided advance on the road to perfect health is marked by acute reactions. The cure invariably proceeds through the darkness and chaos of the crises to the light and beauty of perfect health, periods of marked improvement alternating with acute eliminating activity (the "spiritual temptations" and "combats" of Swedenborg), until perfect regeneration has taken place. Chapter XXI Periodicity In many forms of acute disease, crises develop with marked regularity and in well-defined periodicity. This phenomenon has been observed and described by many physicians. It is not so well known, however, that in the cure of chronic diseases also, crises develop in accordance with certain laws of periodicity. Periodicity is governed by the Septimal Law or Law of Sevens, which seems to be the basic law governing the vibratory activities of the planetary universe. The harmonics of heat, light, sound, electricity, magnetism and of atomic structure and arrangement run in scales of seven. The Law of Sevens governs the days of the week, the phases of the moon and the menstrual periods of the woman. Every observing physician is aware of its influence on feverish, nervous and psychic diseases. The Law of Sevens dominates the life of individuals and of nations and of everything that lives and has periods of birth, growth, fruitage and decline. Over two thousand years ago Pythagoras and Hippocrates distinctly recognized and proclaimed the Law of Crises in its bearing on the cure of chronic diseases. They taught that alternating, well-defined periods of improvement and of crises were determined and governed by the law of periodicity and by the law of numbers (the Septimal Law). The following quotations are taken from the ~Encyclopedia Britannica,~ Vol. XV, p. 800: "But this artistic completeness was closely connected with 'the third cardinal virtue' of Hippocratic medicine--the clear recognition of disease as being equally with life a process governed by what we should now call natural laws, which could be known by observation and which indicated the spontaneous and normal direction of recovery, by following which alone could the physician succeed.