The writer begins his book by naming, in his mystical manner, the three "books" (that is to say, three systems of educating humanity) which God has established; they are instruction by means of the world, by means of man, and by means of universal "light" (or enlightenment). Education by means of the world has failed, as worldly wisdom, atheism, and epicureanism, introduced by Satan, have crazed men's minds. Instruction from man by means of laws and punishment, and the endeavours of philosophers and founders of sects, has also resulted in failure; all attempts to amend humanity by human means have had no result, for they were isolated and relied on violent means. There remains a third "school," the only successful one, which instructs by means of the "universal light." This light, or rather enlightenment, consists in the complete collection of God's revelations to man by means of Scripture, which through God's power will become intelligible to all. There is no doubt that this "universal light" will one day appear to the whole world. Komenský quotes the Revelation of St. John in support of this statement. He then proceeds to define this light, which is "a brightness that flows on things, discloses and discovers them, and through the influence of which spectators realise shapes, positions, movements, the distances of things, and their reciprocal relations." Light is threefold--eternal, exterior, and interior light. Besides the eternal divine light, there is the exterior light proceeding from the sun and the stars.[117] The interior light illuminates the mind, will, and heart of man. The interior light passes through seven gradations, the last of which, immediately preceding the end of the world and to be expected shortly, is "panharmony." The state of "panharmony" will be shortly attained, and we must prepare for it. This should be done mainly by the foundation of a universal academy, a universal language, and universal schools. When all this has been done, the whole world will be "one race, one people, one house, one school of God. The heathens will be converted. The Jews will perceive that they are still in darkness. All lands will become subject to God and Christ. In accordance with the Revelations and the Acts of the Apostles, Satan will be taken prisoner and shown in triumph. The whole world will have peace; (there will be) one truth, one heart, one path. Thus will Christ's prophecy of 'one shepherd, one flock' be fulfilled. This will be the true Golden Age. It will be the Sabbath of the Church, the seventh period of the world, preceding the octave that will resound in happy eternity."[118]