763. It is according to order that a first should go forth to its last both in general and in particular, in order that variety may exist in all things, and through varieties every quality; for quality is perfected by means of differences relating to what is more or less opposite. Who cannot see that truth takes on its quality through the existence of falsity, and good likewise through the existence of evil, as light takes on its quality through the existence of darkness, and heat through the existence of cold? What would color be if there were no black and nothing but white? If it were otherwise the quality of intermediate colors could not but be imperfect. What is sensation apart from relation; and what is relation except to things opposite? Is not the sight of the eye obscured by looking at white only, and quickened by a color that inwardly derives something from black, such, for example, as green? Is not the sense of bearing dulled by the continued strain of one tone upon its organs, and stimulated by a modulation that is varied by relative sounds? What is the beautiful without relation to the unbeautiful? So in some pictures in order to present vividly the beauty of a virgin, an ugly face is placed beside the handsome one. What are joy and happiness without relation to what is joyless and unhappy? Will not one become insane by dwelling upon one idea only, uninterrupted by a variety that tends to things opposite? It is the same with the spiritual things of the church, the opposites of which have relation to evil and falsity, which, nevertheless, are not from the Lord, but from man who has freedom of choice which he can turn either to a good use or an evil use; comparatively as it is with darkness and cold, which are not from the sun but are from the earth, which by its revolutions in turn withdraws from the sun and returns to it; and without its turning from and to the sun there would be neither day nor year, consequently no person and no thing on the earth. I have heard that churches which are in different goods and truths, provided their goods relate to love to the Lord, and their truths to faith in Him, are like so many gems in a king's crown.