And the principles on which this division is to be made, are as regards relation of quantities, the same in architecture as in painting, or indeed, in any other art whatsoever, only the painter is by his varied subject partly permitted, partly compelled, to dispense with the symmetry of architectural light and shade, and to adopt arrangements apparently free and accidental. So that in modes of grouping there is much difference (though no opposition) between the two arts; but in rules of quantity, both are alike, so far forth as their commands of means are alike. For the architect, not being able to secure always the same depth or decision of shadow, nor to add to its sadness by color (because even when color is employed, it cannot follow the moving shade), is compelled to make many allowances, and avail himself of many contrivances, which the painter needs neither consider nor employ. XIII. Of these limitations the first consequence is, that positive shade is a more necessary and more sublime thing in an architect's hands than in a painter's. For the latter being able to temper his light with an under-tone throughout, and to make it delightful with sweet color, or awful with lurid color, and to represent distance, and air, and sun, by the depth of it, and fill its whole space with expression, can deal with an enormous, nay, almost with an universal extent of it, and the best painters most delight in such extent; but as light, with the architect, is nearly always liable to become full and untempered sunshine seen upon solid surface, his only rests, and his chief means of sublimity, are definite shades. So that, after size and weight, the Power of architecture may be said to depend on the quantity (whether measured in space or intenseness) of its shadow; and it seems to me, that the reality of its works, and the use and influence they have in the daily life of men (as opposed to those works of art with which we have nothing to do but in times of rest or of pleasure) require of it that it should express a kind of human sympathy, by a measure of darkness as great as there is in human life: and that as the great poem and great fiction generally affect us most by the majesty of their masses of shade, and cannot take hold upon us if they affect a continuance of lyric sprightliness, but must be serious often, and sometimes melancholy, else they do not express the truth of this wild world of ours; so there must be, in this magnificently human art of architecture, some equivalent expression for the trouble and wrath of life, for its sorrow and its mystery: and this it can only give by depth or diffusion of gloom, by the frown upon its front, and the shadow of its recess. So that Rembrandtism is a noble manner in architecture, though a false one in painting; and I do not believe that ever any building was truly great, unless it had mighty masses, vigorous and deep, of shadow mingled with its surface.