"Since we have no statement in the Constitution of a required Quorum,..."
I thought that the Quorum requirement was in the US Constitution,
Article One, Section Five - Membership, quorum, ajournments, rules; Power to punish or expel; the Journal.
Each House shall be the Judge of the Elections, Returns and Qualifications of its own Members, and a Majority of each shall constitute a Quorum to do Business; but a smaller Number may adjourn from day to day, and may be authorized to compel the Attendance of absent Members, in such Manner, and under such Penalties as each House may provide.
Seems as if the Quorum requirement is both defined and mandated by the US Federal Constitution...
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