Probably “the whole number of Senators” is equivalent to the term “House.” But what is the “House”?
The Senate de jure consists of two Senators from each State.
The Senate de facto may consist of Senators actually elected and qualified, or of Senators actually elected.
Whether the “House” shall be the Senate de jure or the Senate de facto is now within our discretion. The question has been raised, and the way is open to adopt either interpretation, according to the meaning of the Constitution as seen in the light of Parliamentary Law, and, I add also, of convenience.
According to Parliamentary Law, the whole question is in our hands.
According to convenience, the quorum should be founded on the actual Senate, being the Senators actually elected and qualified.
If ever the argument of convenience was strong, peculiarly strong, it is now, when a wicked rebellion has undertaken to withdraw the Senators of eleven States, thus reducing our numbers. It is not necessary to assert that these States should be no longer counted among our stars. It is enough, if we declare that their vacant chairs shall no longer be counted in our quorum. As the language of the Constitution is drawn into debate, I cannot doubt, that, according to Parliamentary Law, the present question is within the control of the Senate, to be determined by the teachings of reason and convenience, so as to assure the public welfare. Any other interpretation must leave the Senate to all the hazards of disorganization by treason, or, it may be, by indifference. If the Senate declines to exercise this power, it will abandon an essential principle of self-defence.
An extreme case might be put, where, through defection, the actual Senators are reduced to a mere handful. But the rule is not to be tried by any such extreme case, which can occur only when the Government is broken up.
I rest confidently on the double conclusion: first, that the words of the Constitution with regard to the quorum of the Senate, so far as doubtful, are to be interpreted by Parliamentary Law; and, secondly, that, by Parliamentary Law, these words are within the control of the Senate, to be interpreted according to its own ample discretion under the exigency of the occasion.