The Notebooks of Leonardo Da Vinci — Complete
And surely if this Necromancy did exist, as is believed by small
wits, there is nothing on the earth that would be of so much
importance alike for the detriment and service of men, if it were
true that there were in such an art a power to disturb the calm
serenity of the air, converting it into darkness and making
coruscations or winds, with terrific thunder and lightnings rushing
through the darkness, and with violent storms overthrowing high
buildings and rooting up forests; and thus to oppose armies,
crushing and annihilating them; and, besides these frightful storms
may deprive the peasants of the reward of their labours.--Now what
kind of warfare is there to hurt the enemy so much as to deprive him
of the harvest? What naval warfare could be compared with this? I
say, the man who has power to command the winds and to make ruinous
gales by which any fleet may be submerged, --surely a man who could
command such violent forces would be lord of the nations, and no
human ingenuity could resist his crushing force. The hidden
treasures and gems reposing in the body of the earth would all be
made manifest to him. No lock nor fortress, though impregnable,
would be able to save any one against the will of the necromancer.
He would have himself carried through the air from East to West and
through all the opposite sides of the universe. But why should I
enlarge further upon this? What is there that could not be done by
such a craftsman? Almost nothing, except to escape death. Hereby I
have explained in part the mischief and the usefulness, contained in
this art, if it is real; and if it is real why has it not remained
among men who desire it so much, having nothing to do with any
deity? For I know that there are numberless people who would, to
satisfy a whim, destroy God and all the universe; and if this
necromancy, being, as it were, so necessary to men, has not been
left among them, it can never have existed, nor will it ever exist
according to the definition of the spirit, which is invisible in
substance; for within the elements there are no incorporate things,
because where there is no body, there is a vacuum; and no vacuum can
exist in the elements because it would be immediately filled up.
Turn over.
1214.
OF SPIRITS.
We have said, on the other side of this page, that the definition of
a spirit is a power conjoined to a body; because it cannot move of
its own accord, nor can it have any kind of motion in space; and if
you were to say that it moves itself, this cannot be within the
elements. For, if the spirit is an incorporeal quantity, this
quantity is called a vacuum, and a vacuum does not exist in nature;
and granting that one were formed, it would be immediately filled up
by the rushing in of the element in which the vacuum had been
generated. Therefore, from the definition of weight, which is
this--Gravity is an accidental power, created by one element being
drawn to or suspended in another--it follows that an element, not
weighing anything compared with itself, has weight in the element
above it and lighter than it; as we see that the parts of water have
no gravity or levity compared with other water, but if you draw it
up into the air, then it would acquire weight, and if you were to
draw the air beneath the water then the water which remains above
this air would acquire weight, which weight could not sustain itself
by itself, whence collapse is inevitable. And this happens in water;
wherever the vacuum may be in this water it will fall in; and this
would happen with a spirit amid the elements, where it would
continuously generate a vacuum in whatever element it might find
itself, whence it would be inevitable that it should be constantly
flying towards the sky until it had quitted these elements.
AS TO WHETHER A SPIRIT HAS A BODY AMID THE ELEMENTS.
We have proved that a spirit cannot exist of itself amid the
elements without a body, nor can it move of itself by voluntary
motion unless it be to rise upwards. But now we will say how such a
spirit taking an aerial body would be inevitably melt into air;
because if it remained united, it would be separated and fall to
form a vacuum, as is said above; therefore it is inevitable, if it
is to be able to remain suspended in the air, that it should absorb
a certain quantity of air; and if it were mingled with the air, two
difficulties arise; that is to say: It must rarefy that portion of
the air with which it mingles; and for this cause the rarefied air
must fly up of itself and will not remain among the air that is
heavier than itself; and besides this the subtle spiritual essence
disunites itself, and its nature is modified, by which that nature
loses some of its first virtue. Added to these there is a third
difficulty, and this is that such a body formed of air assumed by
the spirits is exposed to the penetrating winds, which are
incessantly sundering and dispersing the united portions of the air,
revolving and whirling amidst the rest of the atmosphere; therefore
the spirit which is infused in this
1215.
air would be dismembered or rent and broken up with the rending of
the air into which it was incorporated.
AS TO WHETHER THE SPIRIT, HAVING TAKEN THIS BODY OF AIR, CAN MOVE OF
ITSELF OR NOT.
It is impossible that the spirit infused into a certain quantity of
air, should move this air; and this is proved by the above passage
where it is said: the spirit rarefies that portion of the air in
which it incorporates itself; therefore this air will rise high
above the other air and there will be a motion of the air caused by
its lightness and not by a voluntary movement of the spirit, and if
this air is encountered by the wind, according to the 3rd of this,
the air will be moved by the wind and not by the spirit incorporated
in it.
AS TO WHETHER THE SPIRIT CAN SPEAK OR NOT.
In order to prove whether the spirit can speak or not, it is
necessary in the first place to define what a voice is and how it is
generated; and we will say that the voice is, as it were, the
movement of air in friction against a dense body, or a dense body in
friction against the air,--which is the same thing. And this
friction of the dense and the rare condenses the rare and causes
resistance; again, the rare, when in swift motion, and the rare in
slow motion condense each other when they come in contact and make a
noise and very great uproar; and the sound or murmur made by the
rare moving through the rare with only moderate swiftness, like a
great flame generating noises in the air; and the tremendous uproar
made by the rare mingling with the rare, and when that air which is
both swift and rare rushes into that which is itself rare and in
motion, it is like the flame of fire which issues from a big gun and
striking against the air; and again when a flame issues from the
cloud, there is a concussion in the air as the bolt is generated.
Therefore we may say that the spirit cannot produce a voice without
movement of the air, and air in it there is none, nor can it emit
what it has not; and if desires to move that air in which it is
incorporated, it is necessary that the spirit should multiply
itself, and that cannot multiply which has no quantity. And in the
4th place it is said that no rare body can move, if it has not a
stable spot, whence it may take its motion; much more is it so when
an element has to move within its own element, which does not move
of itself, excepting by uniform evaporation at the centre of the
thing evaporated; as occurs in a sponge squeezed in the hand held
under water; the water escapes in every direction with equal
movement through the openings between the fingers of the hand in
which it is squeezed.
As to whether the spirit has an articulate voice, and whether the
spirit can be heard, and what hearing is, and seeing; the wave of
the voice passes through the air as the images of objects pass to
the eye.
Nonentity.
1216.
Every quantity is intellectually conceivable as infinitely
divisible.
[Amid the vastness of the things among which we live, the existence
of nothingness holds the first place; its function extends over all
things that have no existence, and its essence, as regards time,
lies precisely between the past and the future, and has nothing in
the present. This nothingness has the part equal to the whole, and
the whole to the part, the divisible to the indivisible; and the
product of the sum is the same whether we divide or multiply, and in
addition as in subtraction; as is proved by arithmeticians by their
tenth figure which represents zero; and its power has not extension
among the things of Nature.]
[What is called Nothingness is to be found only in time and in
speech. In time it stands between the past and future and has no
existence in the present; and thus in speech it is one of the things
of which we say: They are not, or they are impossible.]
With regard to time, nothingness lies between the past and the
future, and has nothing to do with the present, and as to its nature
it is to be classed among things impossible: hence, from what has
been said, it has no existence; because where there is nothing there
would necessarily be a vacuum.
[Footnote: Compare No. 916.]
Reflections on Nature (1217-1219).
1217.
EXAMPLE OF THE LIGHTNING IN CLOUDS.
[O mighty and once living instrument of formative nature. Incapable
of availing thyself of thy vast strength thou hast to abandon a life
of stillness and to obey the law which God and time gave to
procreative nature.]
Ah! how many a time the shoals of terrified dolphins and the huge
tunny-fish were seen to flee before thy cruel fury, to escape;
whilst thy fulminations raised in the sea a sudden tempest with
buffeting and submersion of ships in the great waves; and filling
the uncovered shores with the terrified and desperate fishes which
fled from thee, and left by the sea, remained in spots where they
became the abundant prey of the people in the neighbourhood.
[Footnote: The character of the handwriting points to an early
period of Leonardo's life. It has become very indistinct, and is at
present exceedingly difficult to decipher. Some passages remain
doubtful.]
O time, swift robber of all created things, how many kings, how many
nations hast thou undone, and how many changes of states and of
various events have happened since the wondrous forms of this fish
perished here in this cavernous and winding recess. Now destroyed by
time thou liest patiently in this confined space with bones stripped
and bare; serving as a support and prop for the superimposed
mountain.
[Footnote: Compare No. 1339, written on the same sheet.]
1218.
The watery element was left enclosed between the raised banks of the
rivers, and the sea was seen between the uplifted earth and the
surrounding air which has to envelope and enclose the complicated
machine of the earth, and whose mass, standing between the water and
the element of fire, remained much restricted and deprived of its
indispensable moisture; the rivers will be deprived of their waters,
the fruitful earth will put forth no more her light verdure; the
fields will no more be decked with waving corn; all the animals,
finding no fresh grass for pasture, will die and food will then be
lacking to the lions and wolves and other beasts of prey, and to men
who after many efforts will be compelled to abandon their life, and
the human race will die out. In this way the fertile and fruitful
earth will remain deserted, arid and sterile from the water being
shut up in its interior, and from the activity of nature it will
continue a little time to increase until the cold and subtle air
being gone, it will be forced to end with the element of fire; and