DEAR SIR,--I received only two days ago your favor of the 12th, and as it was on the eve of the return of our post, it was not possible to make so prompt a despatch of the answer. Of all the doctrines which have ever been broached by the federal government, the novel one, of the common law being in force and cognizable as an existing law in their courts, is to me the most formidable. All their other assumptions of un-given powers have been in the detail. The bank law, the treaty doctrine, the sedition act, alien act, the undertaking to change the State laws of evidence in the State courts by certain parts of the stamp act, &c., &c., have been solitary, unconsequential, timid things, in comparison with the audacious, barefaced and sweeping pretension to a system of law for the United States, without the adoption of their Legislature, and so infinitively beyond their power to adopt. If this assumption be yielded to, the State courts may be shut up, as there will then be nothing to hinder citizens of the same State suing each other in the federal courts in every case, as on a bond for instance, because the common law obliges payment of it, and the common law they say is their law. I am happy you have taken up the subject; and I have carefully perused and considered the notes you enclosed, and find but a single paragraph which I do not approve. It is that wherein (page two) you say, that laws being emanations from the legislative department, and, when once enacted, continuing in force from a presumption that their will so continues, that that presumption fails and the laws of course fall, on the destruction of that legislative department. I do not think this is the true bottom on which laws and the administering them rest. The whole body of the nation is the sovereign legislative, judiciary and executive power for itself. The inconvenience of meeting to exercise these powers in person, and their inaptitude to exercise them, induce them to appoint special organs to declare their legislative will, to judge and to execute it. It is the will of the nation which makes the law obligatory; it is their will which creates or annihilates the organ which is to declare and announce it. They may do it by a single person, as an Emperor of Russia, (constituting his declarations evidence of their will,) or by a few persons, as the aristocracy of Venice, or by a complication of councils, as in our former regal government, or our present republican one. The law being law because it is the will of the nation, is not changed by their changing the organ through which they choose to announce their future will; no more than the acts I have done by one attorney lose their obligation by my changing or discontinuing that attorney. This doctrine has been, in a certain degree, sanctioned by the federal executive. For it is precisely that on which the continuance of obligation from our treaty with France was established, and the doctrine was particularly