Periods during which Reason rules at least in name and is treated with the obsequious reverence which the model citizen has, or feigns to have, for his sovereign, are followed by others in which Instinct revolts; rebels dethrone Reason and set up Instinct in its place, or, as they call it, passion and nature. The parties which in turn wield power in these periodic revolutions may be briefly termed classical and romantic. The classicists are the legitimist supporters of Reason; the romanticists are revolutionaries, and their leaders are men like Cleon or Jack Cade, Cromwell, Washington or Robespierre; that is to say, rude demagogues or subtle dialecticians in favour of Instinct. Among the legitimists in Reason as in politics, are to be found those who maintain the divine right, who base the right of Reason to rule over Instinct upon the Will of God, and others again, the constitutionalists, who base their support on the Will of the people, on universal suffrage, who force upon Instinct the law promulgated by society. I need not carry the metaphor to extremes. Every reader can work it out in all its details. I only wanted to show quite clearly that almost all moral philosophers conceived Morality as a struggle between Reason and Instinct, as the defeat of lawlessness by law. But their views diverge widely when they try to explain the source of this law and its claim to obedience. The theologians find no difficulty in this explanation. Just as the essence of Morality according to their ideas is the nearest possible approximation to divine perfection, so the moral law is one enacted by God Himself, and it is a sin punishable with hell fire to fail to observe it or to rebel against it. Others look upon Man as his own law-giver, and trace his moral conduct, his willingness to combat his own instincts, to an inner voice which teaches him what is right. They call this inner voice by different names. They call it Nature, Reason or Conscience, and look upon it as something innate, as a normal constituent of man's psychic nature. That is the meaning of Fichte's apodictic statement: "That which does not meet with the approval of one's own conscience is necessarily sin. Therefore he who acts on anyone else's authority acts in a conscienceless manner."