Thomas Aquinas is usually studied as a metaphysician, this is not the reading given to him by three Renaissance philosophers. At the turn of the sixteenth century there were at least two schools of Thomists, one influenced by Avicenna and Scotus, and the other influenced by Averroes, a reading of Aristotle and Thomas Aquinas himself. The discussion below traces how the interpretation of Thomas' De ente et essentia was changed from being a text for metaphysics to one used for physics. One of the meanings of ens-being-was as a term that was coterminous with the object. As a result, the debate over the first thing thought or the De primo cognito debate centered around the meaning for the term ens, the following essay demonstrates how it moved from metaphysics to physics.