You ask my opinion on the question, whether the States can add any qualifications to those which the constitution has prescribed for their members of Congress? It is a question I had never before reflected on; yet had taken up an off-hand opinion, agreeing with your first, that they could not: that to add new qualifications to those of the constitution, would be as much an alteration, as to detract from them. And so I think the House of Representatives of Congress decided in some case; I believe that of a member from Baltimore. But your letter having induced me to look into the constitution, and to consider the question a little, I am again in your predicament, of doubting the correctness of my first opinion. Had the constitution been silent, nobody can doubt but that the right to prescribe all the qualifications and disqualifications of those they would send to represent them, would have belonged to the State. So also the constitution might have prescribed the whole, and excluded all others. It seems to have preferred the middle way. It has exercised the power in part, by declaring some disqualifications, to wit, those of not being twenty-five years of age, of not having been a citizen seven years, and of not being an inhabitant of the State at the time of election. But it does not declare, itself, that the member shall not be a lunatic, a pauper, a convict of treason, of murder, of felony, or other infamous crime, or a non-resident of his district; nor does it prohibit to the State the power of declaring these, or any other disqualifications which its particular circumstances may call for: and these may be different in different States. Of course, then, by the tenth amendment, the power is reserved to the State. If, wherever the constitution assumes a single power out of many which belong to the same subject, we should consider it as assuming the whole, it would vest the General Government with a mass of powers never contemplated. On the contrary, the assumption of particular powers seems an exclusion of all not assumed. This reasoning appears to me to be sound; but, on so recent a change of view, caution requires us not to be too confident, and that we admit this to be one of the doubtful questions on which honest men may differ with the purest motives; and the more readily, as we find we have differed from ourselves on it.