All the arguments in favor of slavery, that have heretofore been drawn from this clause of the constitution, have been founded on the assumption, that if an act of a legislature did but purport to "hold persons to service or labor"--no matter how, on what conditions, or for what cause--that fact alone was sufficient to make the act constitutional. The entire sum of the argument, in favor of slavery, is but this, viz. the constitution recognizes the constitutionality of "laws" that "hold persons to service or labor,"--slave acts "hold persons to service or labor,"--therefore slave acts must be constitutional. This profound syllogism is the great pillar of slavery in this country. It has, (if we are to judge by results,) withstood the scrutiny of all the legal acumen of this nation for fifty years and more. If it should continue to withstand it for as many years as it has already done, it will then be time to propound the following, to wit: The state constitutions recognize the right of men to acquire property; theft, robbery, and murder are among the modes in which property may be acquired; therefore theft, robbery, and murder are recognized by these constitutions as lawful. No doubt the clause contemplates that there may be constitutional "laws," under which persons may be "held to service or labor." But it does not follow, therefore, that every act, that purports to hold "persons to service or labor," is constitutional. We are obliged, then, to determine whether a statute be constitutional, before we can determine whether the "service or labor" required by it, is sanctioned by the constitution as being lawfully required. The simple fact, that the statute would "hold persons to service or labor," is, _of itself_, no evidence, either for or against its constitutionality. Whether it be or be not constitutional, may depend upon a variety of contingencies--such as the kind of service or labor required, and the conditions on which it requires it. Any service or labor, that is inconsistent with the duties which the constitution requires of the people, is of course not sanctioned by this clause of the constitution as being lawfully required. Neither, of course, is the requirement of service or labor, _on any conditions, that are inconsistent with any rights that are secured to the people by the constitution_, sanctioned by the constitution as lawful. Slave laws, then, can obviously be held to be sanctioned by this clause of the constitution, only by gratuitously assuming, 1st, that the constitution neither confers any rights, nor imposes any duties, upon the people of the United States, inconsistent with their being made slaves; and, 2d, that it sanctions the general principle of holding "persons to service or labor" arbitrarily, without contract, without compensation, and without the charge of crime. If this be really the kind of constitution that has been in force since 1789, it is somewhat wonderful that there are so few slaves in the country.