Debate over proper methods of constitutional interpretation is interminable, in part because the Constitution seems not to tell us how it should be interpreted. I argue here that this appearance is misleading. The Constitution repeatedly refers to itself with the phrase “this Constitution,” and claims to make itself supreme law of the land. Debates over what should be supreme for constitutional interpretation can be resolved if but only if, we have a sufficiently-detailed understanding of what the Constitution is. I consider seven possibilities for what might be the interpretively-supreme “Constitution”: (1) the original expected applications;(2) the original ultimate purposes;(3) the original textually-expressed meaning or Fregean sense (t...