During Pennsylvania's ratifying convention in late-1787, James Wilson stated, "the power of the Constitution predominates. Any thing, therefore, that shall be enacted by Congress contrary thereto, will not have the force of law."
The Federalist Papers
In Federalist No. 33, Alexander Hamilton writes about the Supremacy Clause that federal laws by definition must be supreme. If the laws do not function from that position then they amount to nothing, noting that "A law, by the very meaning of the term, includes supremacy. It is a rule which those to whom it is prescribed are bound to observe. This results from every political association. If individuals enter into a state of society, the laws of that society must be the supreme regulator of their conduct. If a number of political societies enter into a larger political society, the laws which the latter may enact, pursuant to the powers entrusted to it by its constitution, must necessarily be supreme over those societies, and the individuals of whom they are composed."
In Federalist No. 44, James Madison defends the Supremacy Clause as vital to the functioning of the nation. He noted that state legislatures were invested with all powers not specifically defined in the Constitution, but also said that having the federal government subservient to various state constitutions would be an inversion of the principles of government, concluding that if supremacy were not established "it would have seen the authority of the whole society everywhere subordinate to the authority of the parts; it would have seen a monster, in which the head was under the direction of the members".
Alexander Hamilton, wrote in Federalist #78 that, "There is no position which depends on clearer principles, than that every act of a delegated authority, contrary to the tenor of the commission under which it is exercised, is void. No legislative act, therefore, contrary to the Constitution, can be valid."