  Bonaventure showed how philosophical reasoning works in theology in the very structure of his disputed question On the Mystery of the Trinity. Each question is divided into two articles, the first proven using rational premises and the second proven using premises drawn from faith. In Question 1, for example, God is rationally proven to exist in Art. 1, then shown to be a trinity of persons using arguments based on faith and reason in Art. 2. Theology, then, consists most fundamentally in the understanding that results from joining rational arguments and faith-based arguments  together.[13]  The same mode of reasoning is found in On Reducing the Arts to Theology. Here “reduction” consists in developing analogies that move the mind from the liberal arts to theology and back again. Bonaventure argues for each point by combining one claim based on reason with another based on revelation, as though they were wall and buttress of the cathedral of theology. Philosophical reasoning, then, is an absolutely integral part of Bonaventure’s faith-based theology.