13. It has sometimes been said that love makes the life of man; but this does not mean love separate from wisdom, or good separate from truth, in the cause; for love thus separate, or good thus separate, has no reality. Therefore the love which makes the inmost life of man, the life that is from the Lord, is love and wisdom together. Moreover, the love which makes the life of man regarded as a recipient, is not love separate in the cause, but in the effect. For love can be understood only from its quality, and its quality is wisdom; and its quality or wisdom can exist only from its being (esse), which is love; hence it is that love and wisdom are one. It is the same with good and truth. Now since truth is from good, as wisdom is from love, the two taken together are called love or good; for love in its form is wisdom, and good in its form is truth, and form is the source and the only source of quality. From these considerations it may be evident that good is not in the least good except in so far as it has been united to its truth, and that truth is not in the least truth except in so far as it has been united to its good.