Jean Jacques Rousseau (1712–1778). Social Contract & Discourses. 1913.The Social Contract or Principles of Political Right. Book I.
Chapter VIII. The Civil State
Let us draw up the whole account in terms easily commensurable. What man loses by the social contract is his natural liberty and an unlimited right to everything he tries to get and succeeds in getting; what he gains is civil liberty and the proprietorship of all he possesses. If we are to avoid mistake in weighing one against the other, we must clearly distinguish natural liberty, which is bounded only by the strength of the individual, from civil liberty, which is limited by the general will; and possession, which is merely the effect of force or the right of the first occupier, from property, which can be founded only on a positive title.
We might, over and above all this, add, to what man acquires in the civil state, moral liberty, which alone makes him truly master of himself; for the mere impulse of appetite is slavery, while obedience to a law which we prescribe to ourselves is liberty. But I have already said too much on this head, and the philosophical meaning of the word liberty does not now concern us.