The mystery of the Trinity exhausts the idea of the activity of God within his own interior being, or _ad intra_. The dogma of creation expresses the idea of the activity of God without his own interior being, or _ad extra_. It is an explication of the primitive idea of reason which presents simultaneously to intelligence the absolute and the contingent in their necessary relation of the dependence of the contingent upon the absolute. Being an explication of the rational idea, it is rationally demonstrable, and does not, therefore, belong to the super-intelligible part of the revelation, or that which is believed simply on the veracity of God. That portion of the dogma of creation which is super-intelligible, or revealed truth in the highest sense, relates to the supernatural end to which the creation is determined by the decree of God. Nevertheless, although the idea of creation, once proposed, is demonstrable on purely rational principles, it is fairly and fully proposed to reason under an adequate and explicit conception adequately expressed, only by divine revelation. Wherever this adequate formula of revelation has been lost, the conception has been lost with it, and not even the highest philosophy has restored it. Plato's conception of the formation of the universe went no higher than the impression of divine ideas upon matter eternally self existent. In all philosophy which is not regulated by the principles of revelation, the ideas of necessary being and contingent existence and of the relation between them are more or less confused, and the dogma of creation is corrupted. The pure, theistic conception gives at once the pure conception of creation. Not that the idea of creation can be immediately perceived in the idea of God, which has been shown to be impossible; but that it can be perceived in the idea of God by the medium of the knowledge of finite existences given to the intellect together with the knowledge of infinite being, in the {2} primitive intuition. When the idea of infinite being is fully explicated and demonstrated in the perfect conception of God, the existence of real entities which are not God, and therefore not included in necessary being, being known, the relation of these things extrinsic to the being of God, to the being of God itself, becomes evident in the idea of God. It is evident that they have no necessary self-existence either out of the divine being or in the divine being, and therefore have been brought out of nonentity into entity by the act of God.