On the Sublime and Beautiful/Part III/Chapter 14

THE NEXT property constantly observable in such objects is smoothness: a quality so essential to beauty, that I do not now recollect anything beautiful that is not smooth. In trees and flowers, smooth leaves are beautiful; smooth slopes of earth in gardens; smooth streams in the landscape; smooth coats of birds and beasts in animal beauties; in fine women, smooth skins; and in several sorts of ornamental furniture, smooth and polished surfaces. A very considerable part of the effect of beauty is owing to this quality; indeed the most considerable. For, take any beautiful object, and give it a broken and rugged surface; and however well formed it may be in other respects, it pleases no longer. Whereas, let it want ever so many of the other constituents, if it wants not this, it becomes more pleasing than almost all the others without it. This seems to me so evident, that I am a good deal surprised, that none who have handled the subject have made any mention of the quality of smoothness, in the enumeration of those that go to the forming of beauty. For indeed any ruggedness, any sudden projection, any sharp angle, is in the highest degree contrary to that idea.