In our Theologico-Political Treatise we have treated of natural and civil right, and in our Ethics have explained the nature of wrong-doing, merit, justice, injustice, and lastly, of human liberty. Yet, lest the readers of the present treatise should have to seek elsewhere those points, which especially concern it, I have determined to explain them here again, and give a deductive proof of them...
Every natural thing has by nature as much right, as it has power to exist and operate; since the natural power of every natural thing, whereby it exists and operates, is nothing else but the power of (deus sive Natura), which is absolutely free. By natural right I understand the very laws or rules of nature, in accordance with which everything takes place, in other words, the power of nature itself.