If Aristotle is to be believed, Speculative Philosophy came into being through a dilemma. It has always been evident that if some-«thing» is constantly changing, then it cannot be known as a «thing», for it is not, but always becoming other. And even as early as Heraclitus the Greek thinkers had asserted that the physical world was in a state of constant flux or change. The conclusion was obvious: the phenomenal world was neither the object of knowledge, nor knowable. The problem, however, and the dilemma, is that even though the physical world is indeed constantly changing and cannot therefore, at least theoretically, be known, that world is in fact known. It was, then, as a result of attempting to resolve this speculative problem that the Greeks created a new science which was to become known as Metaphysics. This study examines from an Aristotelian perspective the major thinkers of the transcendentalist school, from Plato to Descartes to Kant, and criticizes their attempt to resolve this dilemma by arguing for the existence of another, non-material level of reality situated beyond or behind this physical or material reality.