Gloria Ruth Frost
Various interpreters of Aquinas’s thought have argued that some feature of
God, such as his power or essence, grounds necessary propositions about creatures.
In this dissertation, I argue for alternate interpretation of Aquinas. I make a textually
based argument for the conclusion that Aquinas held that necessary propositions
about creatures have their ontological grounds in the contingently existing substantial
forms of the created beings themselves. The precise feature of a substantial form that
guarantees the truth of a necessary proposition is its unicity. Aquinas thought that
Man is rational is necessarily true because man and rational signify one form in
reality. In addition to explicating Aquinas’s thinking on the grounds of necessary
propositions, I show how Aquinas thought that these propositions could remain true
even after the creatures that they are about (and their forms) have perished.