d perceive anything,
but the thick darkness rendered this impossible; and after having
remained there some time, two things arose within me, fear and
desire,--fear of the dark and threatening cave, desire to see whether
there were anything marvellous within.

3.

I discover for man the origin of the first and perhaps of the second
cause of his being.

[Sidenote: Leonardo's Studies]

4.

Recognizing as I do that I cannot make use of {5} subject matter which
is useful and delightful, since my predecessors have exhausted the
useful and necessary themes, I shall do as the man who by reason of his
poverty arrives last at the fair, and cannot do otherwise than purchase
what has already been seen by others and not accepted, but rejected by
them as being of little value. I shall place this despised and
rejected merchandise, which remains over after many have bought, on my
poor pack, and I shall go and distribute it, not in the big cities, but
in the poor towns, and take such reward as my goods deserve.

[Sidenote: Vain Knowledge]

5.

All knowledge which ends in words will die as quickly as it came to
life, with the exception of the written word: which is its mechanical
part.

6.

Avoid studies the result of which will die together with him who
studied.

[Sidenote: Value of Knowledge]

7.

The intellect will always profit by the acquisition of any knowledge
whatsoever, for thus what is useless will be expelled from it, and what
is fruitful will remain. It is impossible either to hate or to love a
thing without first acquiring knowledge of it.

{6}

8.

Men of worth naturally desire knowledge.

9.

It is ordained that to the ambitious, who derive no satisfaction from
the gifts of life and the beauty of the world, life shall be a cause of
suffering, and they shall possess neither the profit nor the beauty of
the world.

[Sidenote: On his Contemners]

10.

I know that many will say that this work is useless, and these are they
of whom Demetrius said recked no more of the breath which made the
words proceed from their mouth, than of the wind which proceeded from
their body,--men who seek solely after riches and bodily satisfaction,
men entirely denuded of that wisdom which is the food and verily the
wealth of the soul; because insomuch as the soul is of greater value
than the body, so much greater are the riches of the soul than those of
the body. And often when I see one of these