UNITY, or the production of a whole, is a leading principle of the highest importance, in every art of taste or design, without which no satisfactory result can be realized. This arises from the fact, that the mind can only attend, with pleasure and satisfaction, to one object, or one composite sensation, at the same time. If two distinct objects, or classes of objects, present themselves at once to us, we can only attend satisfactorily to one, by withdrawing our attention for the time from the other. Hence the necessity of a reference to this leading principle of unity.
To illustrate the subject, let us suppose a building, partially built of wood, with square windows, and the remainder of brick or stone, with long and narrow windows. However well such a building may be constructed, or however nicely the different proportions of the edifice may be adjusted, it is evident it can never form a satisfactory whole. The mind can only account for such an absurdity, by supposing it to have been built by two individuals, or at two different times, as there is nothing indicating unity of mind in its composition.
