OF THE LIFE OF THE PAINTER IN THE COUNTRY.

A painter needs such mathematics as belong to painting. And the
absence of all companions who are alienated from his studies; his
brain must be easily impressed by the variety of objects, which
successively come before him, and also free from other cares
[Footnote 6: Leonardo here seems to be speaking of his own method of
work as displayed in his MSS. and this passage explains, at least in
part, the peculiarities in their arrangement.]. And if, when
considering and defining one subject, a second subject
intervenes--as happens when an object occupies the mind, then he
must decide which of these cases is the more difficult to work out,
and follow that up until it becomes quite clear, and then work out
the explanation of the other [Footnote 11: Leonardo here seems to be
speaking of his own method of work as displayed in his MSS. and this
passage explains, at least in part, the peculiarities in their
arrangement.]. And above all he must keep his mind as clear as the
surface of a mirror, which assumes colours as various as those of
the different objects. And his companions should be like him as to
their studies, and if such cannot be found he should keep his
speculations to himself alone, so that at last he will find no more
useful company [than his own].

[Footnote: In the title line Leonardo had originally written _del
pictore filosofo_ (the philosophical painter), but he himself struck
out_filosofo_. Compare in No. 363 _pictora notomista_ (anatomical
painter). The original text is partly reproduced on Pl. CI.]