What we now call Genius begins, not where rules abstractedly taken end, but where known vulgar and trite rules have no longer any place. It must of necessity be, that even works of Genius, like every other effect, as they must have their cause, must likewise have their rules; it cannot be by chance that excellencies are produced with any constancy or any certainty, for this is not the nature of chance; but the rules by which men of extraordinary parts, and such as are called men of Genius, work, are either such as they discover by their own peculiar observations, or of such a nice texture as not easily to admit being expressed in words; especially as artists are not very frequently skilful in that mode of communicating ideas. Unsubstantial, however, as these rules may seem, and difficult as it may be to convey them in writing, they are still seen and felt in the mind of the artist; and he works from them with as much certainty, as if they were embodied, as I may say, upon paper. It is true, these refined principles cannot be always made palpable, like the more gross rules of art; yet it does not follow, but that the mind may be put in such a train, that it shall perceive, by a kind of scientific sense, that propriety, which words, particularly words of unpractised writers, such as we are, can but very feebly suggest. Invention is one of the great marks of genius; but if we consult experience, we shall find that it is by being conversant with the inventions of others, that we learn to invent; as by reading the thoughts of others we learn to think. Whoever has so far formed his taste, as to be able to relish and feel the beauties of the great masters, has gone a great way in his study; for, merely from a consciousness of this relish of the right, the mind swells with an inward pride, and is almost as powerfully affected as if it had itself produced what it admires. Our hearts, frequently warmed in this manner by the contact of those whom we wish to resemble, will undoubtedly catch something of their way of thinking; and we shall receive in our own bosoms some radiation at least of their fire and splendour. That disposition, which is so strong in children, still continues with us, of catching involuntarily the general air and manner of those with whom we are most conversant; with this difference only, that a young mind is naturally pliable and imitative; but in a more advanced state it grows rigid, and must be warmed and softened before it will receive a deep impression.