It is better to imitate [copy] the antique than modern work.

[Footnote 486, 487: These are the only two passages in which
Leonardo alludes to the importance of antique art in the training of
an artist. The question asked in No. 486 remains unanswered by him
and it seems to me very doubtful whether the opinion stated in No.
487 is to be regarded as a reply to it. This opinion stands in the
MS. in a connection--as will be explained later on--which seems to
require us to limit its application to a single special case. At any
rate we may suspect that when Leonardo put the question, he felt
some hesitation as to the answer. Among his very numerous drawings I
have not been able to find a single study from the antique, though a
drawing in black chalk, at Windsor, of a man on horseback (PI.
LXXIII) may perhaps be a reminiscence of the statue of Marcus
Aurelius at Rome. It seems to me that the drapery in a pen and ink
drawing of a bust, also at Windsor, has been borrowed from an
antique model (Pl. XXX). G. G. Rossi has, I believe, correctly
interpreted Leonardo's feeling towards the antique in the following
note on this passage in manzi's edition, p. 501: "Sappiamo dalla
storia, che i valorosi artisti Toscani dell'eta dell'oro dell'arte
studiarono sugli antichi marmi raccolti dal Magnifico LORENZO DE'
MEDICI. Pare che il Vinci a tali monumenti non si accostasse. Quest'
uomo sempre riconosce per maestra la natura, e questo principio lo
stringeva alla sola imitazione di essa"--Compare No. 10, 26--28
footnote.]

The necessity of anatomical knowledge (488. 489).