A priori

A· pri·o·ri

A priori
  1. Characterizing that kind of reasoning which deduces consequences from definitions formed, or principles assumed, or which infers effects from causes previously known; deductive or deductively. The reverse of a posteriori. (Logic)
  2. Applied to knowledge and conceptions assumed, or presupposed, as prior to experience, in order to make experience rational or possible. (Philos.)
    A priori, that is, form these necessities of the mind or forms of thinking, which, though first revealed to us by experience, must yet have preëxisted in order to make experience possible.