Excerpt from The Rudiments of Architecture and Building
Every principle in Art (unlike one in Science) has to be discovered twice; first, by the artist of genius who introduces it into the practice of his art, but would generally be quite unable to state or explain it in words; and secondly, by the critic who translates it into verbal language, and thereby makes it part of the theory of the art. Many centuries may elapse between these two discoveries of the same when, at length, it is absorbed into the theory of the art, it becomes common property, and the practice of it ceases to be a mark of genius, for genius consists in practice out stripping theory. The advance of theory, however, does not narrow the field of genius, but urges it on into a higher sphere. As its secrets are, one by one, wrested from it, so it must wrest others from nature.