| Questions to Consider
Leonardo's Notes on the Cosmos
Leonardo da Vinci
If we consider only his artistic achievements, Leonardo da Vinci
(1452-1519), places in the first rank of notable figures from
the Italian Renaissance. When we delve into his private notebooks,
Leonardo stands out as one of the greatest thinkers in Western
history. Not intended for publication and inscribed in a mirror-image
hand, his notes include drawings, designs, and speculations covering
an extraordinary range of topics and ideas. As a scientist, Leonardo
leaned toward mechanics, not surprising from one of the foremost
engineers of his time. Various fantastic machines, such as the draft
for his "helicopter," capture the imagination of modern students. The
notebooks also display his fascination with natural phenomena, such
as properties of light, the age of trees, birds in flight, and human
anatomy. As we see below, his wide-ranging interests also included
the heavens. Untrained in any formal, scholastic sense on the topic,
Leonardo challenged accepted notions about the nature of the universe
a generation before Polish mathematician Nicolaus Copernicus
(1473-1543) upset ancient and medieval norms.
Questions to Consider
Demonstration that the Earth is a Star
Whom is Leonardo arguing against in this passage? Why does he
seem so irritated?
How do these notes represent a synthesis of observation and
In your discourse you must prove that the earth is a star much
like the moon, and the glory of our universe; and then you must treat
of the size of various stars according to the authors.
The sun does not move.
The sun has substance, shape, motion, radiance, heat, and
generative power: and these qualities all emanate from it without its
Praise of the Sun
The sun has never seen any shadow.
If you look at the stars without their rays (as may be done by
looking at them through a small hole made with the extreme point of a
fine needle and placed so as almost to touch the eye), you will see
these stars to be so minute that it would seem as though nothing
could be smaller; it is in fact the great distance which is the
reason of their diminution, for many of them are very many times
larger than the star which is the earth with the water. Think, then,
what this star of ours would seem like at so great a distance, and
then consider how many stars might be set in longitude and latitude
between these stars which are scattered throughout this dark expanse.
I can never do other than blame many of those ancients who said that
the sun was no larger than it appears; among these being Epicurus;
and I believe that he reasoned thus from the effects of a light
placed in our atmosphere equidistant from the centre; whoever sees it
never sees it diminished in size at any distance.
But I wish I had words to serve me to blame those who would fain
extol the worship of men above that of the sun; for in the whole
universe I do not see a body of greater magnitude and power than
this, and its light illumines all the celestial bodies which are
distributed throughout the universe. All vital force descends from it
since the heat that is in living creatures comes from the soul (vital
spark); and there is no other heat nor light in the universe.
And certainly those who have chosen to worship men as gods such as
Jove, Saturn, Mars, and the like have made a very great error, seeing
that even if a man were as large as our earth he would seem like one
of the least of the stars which appears but a speck in the universe;
and seeing also that men are mortal and subject to decay and
corruption in their tombs.
[Thespera] and Marullo and many others praise the sun.
Selections from the Notebooks of Leonardo
da Vinci, ed. Irma A. Richter (Oxford, England: Oxford University
Press, 1977), 54-55.