Natural Law

 “It appears to me, that the only axiom necessary to establish the science of natural law is this: ‘I exist as a human being, therefore I have a right to exist as a human being.’  This once acknowledged, the rights of men in their various relations as individuals, husbands, or wives, fathers or mothers, as citizens individually and collectively in the state to other independent states and to the collective citizens within the state, may consistently and justly be established.  Though some ancient and modern writers have maintained that no right exists antecedent to the magistracy deriving the right of this from some extra-political, and in some cases even from some extra-human source, it is nevertheless true, that if we do not deny our own existence and the existence of truth, the reality and truth of natural law can be scientifically and irresistibly established with as much certainty as that of other sciences....”

“Natural Law then inquires into the rights of man to be derived from his nature, both physical and moral, for the latter is closely connected with the former; it inquires into quid sit justum aut injustum, not into quid sit juris, (what is law or lawful).  The word nature is a term used in so many various significations, that it has led to great confusion of ideas in several branches; and it is not an uncommon mistake to believe that natural law is that law which existed in the erroneously supposed state of nature, on which, as has been indicated already, I shall have to dwell in the next book.  The law of nature, or natural law, on the contrary is the law, the body of rights, which we deduce from the essential nature of man....”

“Nor are natural law and moral law or ethics the same.  The difference is material.  Ethics treat, among other subjects, of the duties of man, and secondarily of his rights derivable from his duties; natural law, on the other hand, treats, as the fundamental and primary subject, of man’s rights, and secondarily of his obligations flowing from the fact of each man’s being possessed of the same rights.  This distinction, though essential, has been, and to this day is frequently overlooked.  An equally good name with that of natural law, might be abstract law or pure law, as we have pure mathematics.”

-Francis Lieber, Manual of Political Ethics