We may consider also a third kind of relation between the individual and the law, a relation of disobedience to its penalty. This gives rise to the setting up of criminal laws, which, at bottom, are less a particular class of law than the sanction behind all the rest. Along with these three kinds of law goes a fourth, most important of all, which is not graven on tablets of marble or brass, but on the hearts of the citizens. This forms the real constitution of the State, takes on every day new powers, when other laws decay or die out, restores them or takes their place, keeps a people in the ways in which it was meant to go, and insensibly replaces authority by the force of habit. I am speaking of morality, of custom, above all of public opinion; a power unknown to political thinkers, on which none the less success in everything else depends. With this the great legislator concerns himself in secret, though he seems to confine himself to particular regulations; for these are only the arc of the arch, while manners and morals, slower to arise, form in the end its immovable keystone. Among the different classes of laws, the political, which determine the form of the government, are alone relevant to my subject. BOOK III Before speaking of the different forms of government, let us try to fix the exact sense of the word, which has not yet been very clearly explained. CHAPTER I GOVERNMENT IN GENERAL I warn the reader that this chapter requires careful reading, and that I am unable to make myself clear to those who refuse to be attentive. Every free action is produced by the concurrence of two causes; one moral, _i.e._ the will which determines the act; the other physical, _i.e._ the power which executes it. When I walk towards an object, it is necessary first that I should will to go there, and, in the second place, that my feet should carry me. If a paralytic wills to run and an active man wills not to, they will both stay where they are. The body politic has the same motive powers; here too force and will are distinguished, will under the name of legislative power and force under that of executive power. Without their concurrence, nothing is, or should be, done. We have seen that the legislative power belongs to the people, and can belong to it alone. It may, on the other hand, readily be seen, from the principles laid down above, that the executive power cannot belong to the generality as legislature or Sovereign, because it consists wholly of particular acts which fall outside the competency of the law, and consequently of the Sovereign, whose acts must always be laws.