Nature is, and must be the fountain which alone is inexhaustible; and from which all excellencies must originally flow. - Joshua Reynolds

No Art can be grafted with success on another art. For though they all profess the same origin, and to proceed from the same stock, yet each has its own peculiar modes both of imitating nature, and of deviating from it, each for the accomplishment of its own particular purpose. These deviations, more especially, will not bear transplantation to another soil.

A painter must not only be of necessity an imitator of the works of nature...but he must be as necessarily an imitator of the works of other painters: this appears more humiliating, but is equally true; and no man can be an artist, whatever he may suppose, upon any other terms.

Words should be employed as the means, not as the end: language is the instrument, conviction is the work.