truth, on their human or individualistic significance.  The difference between idealism and realism is not more than a question which to choose.  At the further end and last remove, when all art has been resolved into a sensation, an effect, lies impressionism, which, by its nature, is a single phase at a single moment as seen by a single being; but even then, if the mind be normal, if the phase be veritable, if the moment be that of universal beauty which Faust bade be eternal, the artistic work remains ideal; but on the other hand, it is usually the eccentric mind, the abnormal phase, the beauty of morbid sensation that are rendered; and impressionism becomes, as a term, the vanishing-point of realism into the moment of sense.

The world of art, to reach its last limitation, through all this wide range is in each creation passed through the mind of the artist and presented necessarily under all the conditions of his personality.  His nature is a term in the process, and the question of imperfection or of error, known as the personal equation, arises.  Individual differences of perceptive power in comprehending what is seen, and of narrative skill, or in the plastic and pictorial arts of manual dexterity, import this personal element into all artistic works, the more in proportion to the originality of the maker and the fulness of his self-expression.  In rendering from the actual such error is unavoidable, and is practically admitted by all who would rather see for themselves than take the account of a witness, and prefer the original to any copy of it, though they thereby only substitute their own error for that of the artist.  This personal error, however, is easily corrected by the consensus of human nature.

The differences in personality go far deeper than this common liability of humanity to mere mistakes in sight and in representation.  The isolating force that creates a solitude round every man lies in his private experience, and results from his original faculties and the special conditions of his environment, his acquired habits of attending to some things rather than others open to him, the choices he has made in the past by which his view of the world and his interest in it have been determined.  Memory, the mother of the Muses, is supreme here; a man’s memory, which is the treasury of his chosen delights in life, characterizes him, and differentiates his work from that of others, because he must draw on that store for his materials.  Thus a man’s character, or, what is more profound, his temperament, acting in conjunction with the memory it has built up for itself, is a controlling force in artistic work, and modifies it in the sense that it presents the universal truth only as it exists in his personality, in his apprehension of it and its meaning.