Men who, although thus bound down by the almost invincible powers of
early habits, have still exerted extraordinary abilities within their
narrow and confined circle, and have, from the natural vigour of their
mind, given such an interesting expression, such force and energy to
their works, though they cannot be recommended to be exactly imitated,
may yet invite an artist to endeavour to transfer, by a kind of parody,
those excellences to his own works. Whoever has acquired the power of
making this use of the Flemish, Venetian, and French schools is a real
genius, and has sources of knowledge open to him which were wanting to
the great artists who lived in the great age of painting.

To find excellences however dispersed, to discover beauties however
concealed by the multitude of defects with which they are surrounded, can
be the work only of him who, having a mind always alive to his art, has
extended his views to all ages and to all schools, and has acquired from
that comprehensive mass which he has thus gathered to himself, a well
digested and perfect idea of his art, to which everything is referred.
Like a sovereign judge and arbiter of art, he is possessed of that
presiding power which separates and attracts every excellence from every
school, selects both from what is great and what is little, brings home
knowledge from the east and from the west, making the universe tributary
towards furnishing his mind and enriching his works with originality and
variety of inventions.

Thus I have ventured to give my opinion of what appears to me the true
and only method by which an artist makes himself master of his
profession, which I hold ought to be one continued course of imitation,
that is not to cease but with our lives.