190. These are diversions for everyone who is in office or employment. They may therefore be called the diversions of offices or employments. But really they are diversions of the affections from which one engages in his employment. There is an affection in every employment, and it strains the mind, and keeps it intent upon its work or study. This, if it be not relaxed, becomes dull, and its desire flags, as salt that has lost its savor, so that it has no pungency or relish; or as a bended bow, which, unless it be unbent, loses the power that it derives from its elasticity. Just so the mind, kept from day to day in the same ideas, without variety. So the eyes, when they look only at one object, or continually upon one color. For, to look continually at a thing which is black, or continually at red or at white, destroys the sight. Thus, if one looks continually at the snow the sight is destroyed; but it is enlivened if he looks in succession or at the same time upon many colors. Every form delights by its varieties, as a garland of roses of different colors arranged in beautiful order. Hence it is that the rainbow is more charming than the light itself.