In all these arts, purpose is implied—not purpose in the hypothetical sense, as applied to the existence, conditions, and objects, of natural beings—but in the common intelligible sense of the word, as expressing the intention of men in the pursuit of these arts.
Beauty of Useful Objects.
Here the purpose being utility, this kind of beauty arises from the perception of means as adapted to an end, which of course implies, the parts of anything being fitted to answer the purpose of the whole.
This implies an act of understanding and judgment; for of no product of useful art can we perceive the extrinsic beauty, until we know its destination, and the relations which that involves.
When these are known, so powerful is the sense of utility, that, though deviation from the elementary beauty never ceases to be felt, yet that sense sanctions it to a great extent. Hence it is that an irregular dwelling-house may become beautiful, when its convenience is striking. Hence it is that, in the forms of furniture, machines, and instruments, their beauty arises chiefly from this consideration; and that every form becomes beautiful by association, where it is perfectly adapted to its end.
The greater, however, the elementary beauty, that can be introduced in useful objects, the more obvious will their utility be, and the more beautiful will they universally appear. This will be granted the moment I mention simplicity.
Of all the elements of beauty already spoken of—of all the means of producing accordant and agreeable relations—simplicity appears to be the most efficient; and in all the useful arts, no elementary consideration recommends their objects so much.
This implies all the rest, regularity, uniformity, proportion, order, &c., as far as is compatible with purpose.
Thus, in regard to uniformity, says some one, a number of things destined for the same purpose, as chairs, spoons, &c., cannot be too uniform, because they are adapted to uniform purposes; but it would be absurd to give to objects destined for one purpose the form suited to those destined for another.
So also the objects of useful art will resemble in form precisely as they resemble in purpose; and where the purpose is similar, and the deviation which is admissible is slight, this becomes a subject of great nicety, and, if ornament be at the same time admissible, a subject of exquisite taste.