This point may be presented in another light. By the law of nature all men are free. But in some governments the law of the state, upheld by the power of the state, overrides the law of nature, and enslaves a portion of the people. The law of nature recedes before this legalized violence; but it recedes no farther than the legalized violence drives it back. Within the jurisdictional limits of such states, then, slavery is made _legal_, though it is not made _right_. But if a slave passes out of the jurisdiction where violence overpowers right, into a jurisdiction where right is superior to violence, he is then free; not because there is any change in the man, but because there is a change in the laws to which the man is subject. There may, however, be some further positive law which, though it does not authorize the buying or selling of a slave, still does provide that an escaped or escaping slave may be recaptured and redelivered into bondage. Such is the third paragraph of the second section of the fourth article of the constitution of the United States. Such, too, is the act of Congress of February 12, 1793, providing for the recapture of fugitive slaves. This, however, would not be without positive law. The debates in all the conventions for adopting the constitution of the United States, proceed upon the ground that slavery depends upon positive law for its existence. If it did not,--if a man who has a legal right to a slave in Virginia, has a legal right to him anywhere,--then the provision in the constitution, and the act of 1793 for recapturing fugitive slaves, would have been unnecessary. On the south side of a boundary line, then, slavery may exist by force of positive law; while, on the north side, in the absence of any such law, slavery is unlawful. A slave passing out of a jurisdiction where slavery is legalized, into a jurisdiction where it is not, becomes free. It is as though a man should migrate from one of those South Sea islands, where cannibalism is legalized, and where the public authorities, according to the reports of travellers, not only condemn and execute a criminal, _but dine on him, after he is executed_,--it is, I say, as though the subject of such a government should migrate into one where cannibalism is not lawful, and where, therefore, though he should be condemned and executed for crime, it would be no part of the sentence or the ceremony that he should be eaten by his judges. He is out of cannibal jurisdiction.