Chapter XXVIII.--The Fourfold Division of the Mosaic Law.
The Mosaic philosophy is accordingly divided into four parts,--into the historic, and that which is specially called the legislative, which two properly belong to an ethical treatise; and the third, that which relates to sacrifice, which belongs to physical science; and the fourth, above all, the department of theology, "vision,"  which Plato predicates of the truly great mysteries. And this species Aristotle calls metaphysics. Dialectics, according to Plato, is, as he says in The Statesman, a science devoted to the discovery of the explanation of things. And it is to be acquired by the wise man, not for the sake of saying or doing aught of what we find among men (as the dialecticians, who occupy themselves in sophistry, do), but to be able to say and do, as far as possible, what is pleasing to God. But the true dialectic, being philosophy mixed with truth, by examining things, and testing forces and powers, gradually ascends in relation to the most excellent essence of all, and essays to go beyond to the God of the universe, professing not the knowledge of mortal affairs, but the science of things divine and heavenly; in accordance with which follows a suitable course of practice with respect to words and deeds, even in human affairs. Rightly, therefore, the Scripture, in its desire to make us such dialecticians, exhorts us: "Be ye skilful money-changers"  rejecting some things, but retaining what is good. For this true dialectic is the science which analyses the objects of thought, and shows abstractly and by itself the individual substratum of existences, or the power of dividing things into genera, which descends to their most special properties, and presents each individual object to be contemplated simply such as it is.
Wherefore it alone conducts to the true wisdom, which is the divine power which deals with the knowledge of entities as entities, which grasps what is perfect, and is freed from all passion; not without the Saviour, who withdraws, by the divine word, the gloom of ignorance arising from evil training, which had overspread the eye of the soul, and bestows the best of gifts,--
"That we might well know or God or man." 
It is He who truly shows how we are to know ourselves. It is He who reveals the Father of the universe to whom He wills, and as far as human nature can comprehend. "For no man knoweth the Son but the Father, nor the Father but the Son, and he to whom the Son shall reveal Him."  Rightly, then, the apostle says that it was by revelation that he knew the mystery: "As I wrote afore in few words, according as ye are able to understand my knowledge in the mystery of Christ."  "According as ye are able," he said, since he knew that some had received milk only, and had not yet received meat, nor even milk simply. The sense of the law is to be taken in three ways,  --either as exhibiting a symbol, or laying down a precept for right conduct, or as uttering a prophecy. But I well know that it belongs to men [of full age] to distinguish and declare these things. For the whole Scripture is not in its meaning a single Myconos, as the proverbial expression has it; but those who hunt after the connection of the divine teaching, must approach it with the utmost perfection of the logical faculty.