or when it restrains the wanton tendencies of desire to corporeal delight. For in all such operations it manifestly subdues the irrational motions, both gnostic and appetitive, and absolves itself from them, as from things foreign to its nature. But it is necessary to investigate the essence of every thing, not from its perversion, but from its energies according to nature. If therefore reason, when it energizes in us as reason, restrains the shadowy impressions of the delights of licentious desire, punishes the precipitate motion of fury, and reproves the senses as full of deception, asserting that "We nothing accurate, or see, or hear:" and if it says this, looking to its internal reasons, none of which it knows through the body, or through corporeal cognitions, it is evident that, according to this energy, it removes itself far from the senses, contrary to the decision of which it becomes separated from those sorrows and delights. After this, let us direct our attention to another and a better motion of our rational soul, when, during the tranquillity of the inferior parts, by a self-convertive energy, it sees its own essence, the powers which it contains, the harmonic reasons from which it consists, and the many lives of which it is the middle boundary, and thus finds itself to be a rational world, the image of the prior natures, from which it proceeds, but the paradigm of such as are posterior to itself. To this energy of the soul, theoretic arithmetic and geometry greatly contribute, for these remove it from the senses, purify the intellect from the irrational forms of life with which it is surrounded, and lead it to the incorporeal perception of ideas. For if these sciences receive the soul replete with images, and knowing nothing subtile and unattended with material garrulity; and if they elucidate reasons possessing an irrefragable necessity of demonstration, and forms full of all certainty and immateriality, and which by no means call to their aid the inaccuracy of sensibles, do they not evidently purify our intellectual life from things which fill us with a privation of intellect, and which impede our perception of true being?