In republican government the legislative authority necessarily predominates. The remedy for this . . . is to divide the legislature into different branches; and to render them by different modes of election, and different principles of action, as little connected with each other as the nature of their common functions, and their common dependence on the society, will admit.
James MadisonAnother advantage accruing from this ingredient in the constitution of a senate, is the additional impediment it must prove against improper acts of legislation. No law or resolution can now be passed without the concurrence first of a majority of the people, and then of a majority of the states.
James MadisonThe proposed constitution, therefore, even when tested by the rules laid down by its antagonists, is, in strictness, neither a national nor a federal constitution; but a composition of both. In its foundation it is federal, not national; in the sources from which the ordinary powers of the government are drawn, it is partly federal, and partly national; in the operation of these powers, it is national, not federal; in the extent of them again, it is federal, not national; and finally, in the authoritative mode of introducing amendments, it is neither wholly federal, nor wholly national.
James Madison