Let us go back a little in the scale of being, in order to develop this principal more fully. Lifeless matter is capable of indefinite increase in its own order, but this increase has no tendency to elevate it to the grade of vegetative life. A new and different principle of organization must be introduced in order to construct from its simple elements a vegetative form, as, for instance, a flower. So, also, the explication of vegetative life has no tendency to generate a sentient principle. The plant may go on producing foliage, flowering, germinating, and reproducing its species for ever, but its vital activity can never produce a sentient soul, or proceed to that degree of perfection that it requires a sentient soul as its last complement or the form of its organic life. Suppose a plant or flower to receive a sentient soul; this soul must be immediately created by God, and it would be the principle or form of a new life, which, in relation to the natural, vegetative life of the flower, would be _super_-natural, elevating it to an order of life above that which constitutes it a flower. A sentient creature, as a dog or a bird, has no tendency to explicate from the constitutive principle of its animal soul intelligence, or to attain a state of existence in which an intelligent personality is due to it as its last complement. If the animal soul could have an intelligent personality, it must be by hypostatic union with an intelligent nature distinct from itself, which would then become the _suppositum_, or principal of imputability to the animal nature. The animal would then be elevated to a state which would be _super_-natural, relatively to the animal nature, or entirely above the plane of it's natural development. In like manner, the rational nature has no tendency or power to rise above itself, or to do more than explicate that principle which constitutes it rational. If it is elevated to a higher order, it must be by a direct act of omnipotence, an immediate intervention of the creator, producing in it an act which could never be produced by the explication of its rationality, even though it should progress to all eternity. This act is supernatural in the absolute sense. That is, it lies in an order above created nature as a totality, and above all nature which might be created; _supra omnem naturam creatam atque creabilem_.