The fundamental maxim of the mediæval religio-philosophy—Invisibilia non decipiunt, was fertile in delusions. It led men to reject, as untrustworthy, the testimony of sense and of experience. Thus, in the transubstantiation controversy of the ninth century, Realism and Superstition conquered together. It taught them to deduce all knowledge from certain mental abstractions, Platonic Ideas and Aristotelian Forms. Thus Bonaventura (who exhibits this tendency at its height) resolves all science into union with God. The successive attainment of various kinds of knowledge is, in his system, an approximation, stage above stage, to God—a scaling of the heights of Illumination, as we are more closely united with the Divine Word—the repertory of Ideas. Thus, again, the Scriptures were studied by the schoolmen less as a practical guide for the present life than as so much material whence they might deduce metaphysical axioms and propositions—discover more of those divine abstractions which they regarded as the seminal principles of all thought and all existence. They were constantly mistaking results which could only have been attained by revelation or tradition from without, for truth evolved from within the depths of the finite mind, by virtue of its immediate commerce with the Infinite. Anselm found no difficulty in assuming that the God of his ontological proof was identical with the God of the Bible. Note to page 144. Thus, speaking of the angelic state, he says,—Creatura cœli illa est, præsto habens per quod ista intueatur. Videt Verbum, et in Verbo facta per Verbum. Nec opus habet ex his quæ facta sunt, factoris notitiam mendicare.—_De Consid._ V. i., and comp. _Serm. in Cantica_, v. 4.