424. I. THAT THE NATURE OF SCORTATORY LOVE CANNOT BE KNOWN UNLESS THE NATURE OF CONJUGIAL LOVE IS KNOWN. Here, as in no. 423, by scortatory love is meant the love of adultery which destroys conjugial love. That the nature of this scortatory love cannot be known unless the nature of conjugial love is known, has no need of demonstration; it needs only to be illustrated by comparisons. For instance, Who can know what evil and falsity are unless he knows what good and truth are? and who can know what the unchaste is, or the dishonorable, the indecorous, and the ugly, unless he knows what the chaste is, or the honorable, the decorous, and the beautiful? Who can discern insanities save one who is wise, that is, Who knows what Wisdom is? Who can rightly perceive inharmonious stridors save one who by learning and study has absorbed harmonious numbers? In like manner, Who can see clearly the nature of adultery unless he has seen clearly the nature of marriage? or Who can set before his judgment the filthiness of the pleasures of scortatory love unless he has previously set before his judgment the cleanness of conjugial love? Because I have now finished The Delights of wisdom concerning Conjugial Love, therefore, from the intelligence thence acquired, I am able to describe the pleasures [of insanity] from scortatory love.