Seeing that the conclusions above defined (and some to be later drawn), are not entirely in accord with a large part of modern criticism based upon what are commonly described as new and improved forms of the painter's art, it is necessary to refer to these forms, which are generally comprehended under what is known as Impressionism.[c] Alas, to the frailty of man must we ascribe the spread of this movement, which has destroyed so many bright young intellects, and is at this moment leading thousands of gentle spirits along the level path which ends in despair. For the real road of art is steep, and difficult, and long. Year upon year of patient thought, patient observation, and patient toil, lie ahead of every man who covets a crown of success as a painter. He must seek to accumulate vast stores of knowledge of the human form and its anatomy, of nature in her prolific variety, of linear and aerial perspective, of animals which move on land or through the air, of the laws of colours and their combinations. He must sound the depths of poetry, and sculpture, and architecture; absorb the cream of sacred and profane history; and with all these things and many more, he must saturate his mind with the practical details of his art. Every artist whose work the world has learned to admire has done his best to gain this knowledge, and certainly no great design was ever produced by one whose youth and early manhood were not worn with ardent study. For knowledge and experience are the only foundations upon which the imagination can build. Every new conception is a rearrangement of known signs, and the imagination is powerless to arrange them appropriately without a thorough comprehension of their character and significance. [c] The varied interpretations of Impressionism are referred to elsewhere (see page ). When using the term in this book without qualification, the writer means thereby the subordination of design to colour, which definition covers all the forms of the "new art" without going beyond any of them.