The Theory of Moral Sentiments by Adam Smith

That utility is one of the principal sources of beauty has been observed by everybody, who has considered with any attention what constitutes the nature of beauty. The conveniency of a house gives pleasure to the spectator as well as its regularity, and he is as much hurt when he observes the contrary defect, as when he sees the correspondent windows of different forms, or the door not placed exactly in the middle of the building. That the fitness of any system or machine to produce the end for which it was intended, bestows a certain propriety and beauty upon the whole, and renders the very thought and contemplation of it agreeable, is so obvious that nobody has overlooked it.

The cause too, why utility pleases, has of late been assigned by an ingenious and agreeable philosopher, who joins the greatest depth of thought to the greatest elegance of expression, and possesses the singular and happy talent of treating the abstrusest subjects not only with the most perfect perspicuity, but with the most lively eloquence. The utility of any object, according to him, pleases the master by perpetually suggesting to him the pleasure or conveniency which it is fitted to promote. Every time he looks at it, he is put in mind of this pleasure; and the object in this manner becomes a source of perpetual satisfaction and enjoyment. The spectator enters by sympathy into the sentiments of the master, and necessarily views the object under the same agreeable aspect. When we visit the palaces of the great, we cannot help conceiving the satisfaction we should enjoy if we ourselves were the masters, and were possessed of so much artful and ingeniously contrived accommodation. A similar account is given why the appearance of inconveniency should render any object disagreeable both to the owner and to the spectator.