Philosophy
Experience, Nature, and the Pursuit of Truth
Nature is full of infinite causes which were never set forth in experience.
— Leonardo da Vinci
Overview
Leonardo's philosophical writings are scattered throughout his notebooks, appearing as aphorisms, reflections, and sudden bursts of insight between technical diagrams and shopping lists. He was not a systematic philosopher in the academic sense, but his thought is remarkably consistent: experience over authority, nature as the ultimate teacher, and a deep awareness of the passage of time.
These passages reveal Leonardo at his most personal. They are the thoughts of a man who spent decades watching, drawing, and thinking — and who knew that time was consuming his life as surely as it consumed everything else.
On Time
Leonardo's recurring obsession
We have no lack of system or device to measure and to parcel out these poor days of ours; wherein it should be our pleasure that they be not squandered or suffered to pass away in vain, and without meed of honour, leaving no record of themselves in the minds of men; to the end that this our poor course may not be sped in vain.
C.A. 12 v. a
O Time, thou that consumest all things! O envious age, thou destroyest all things and devourest all things with the hard teeth of the years, little by little, in slow death! Helen, when she looked in her mirror and saw the withered wrinkles which old age had made in her face, wept, and wondered to herself why ever she had twice been carried away.
C.A. 71 r. a
The age as it flies glides secretly and deceives one and another; nothing is more fleeting than the years, but he who sows virtue reaps honour.
C.A. 71 v. a
Wrongfully do men lament the flight of time, accusing it of being too swift, and not perceiving that its period is yet sufficient; but good memory wherewith Nature has endowed us causes everything long past to seem present.
The Helen of Troy passage borrows from Ovid's Metamorphoses (XV:232-6), but Leonardo restructures it, using the apostrophe to Time as both prelude and finale — a musical technique applied to prose. Scholar Gerolamo Calvi identified the source in 1916 and noted that Leonardo had a copy of Ovid in his possession. The passage about memory is pure Leonardo: time is not too swift — your memory just makes the past seem closer than it is. -D
On Experience and Nature
Leonardo's epistemology
Experience the interpreter between resourceful nature and the human species teaches that that which this nature works out among mortals constrained by necessity cannot operate in any other way than that in which reason which is its rudder teaches it to work.
C.A. 86 r. a
There is no result in nature without a cause; understand the cause and you will have no need of the experiment.
C.A. 147 v. a
Experience is never at fault; it is only your judgment that is in error in promising itself such results from experience as are not caused by our experiments.
Wrongly do men cry out against experience and with bitter reproaches accuse her of deceitfulness. Let experience alone, and rather turn your complaints against your own ignorance, which causes you to be so carried away by your vain and insensate desires as to expect from experience things which are not within her power!
C.A. 154 r. c
"Experience is never at fault; it is only your judgment that is in error." This is Leonardo's foundational principle — and it's essentially the scientific method stated in a single sentence. Don't blame the data; blame your interpretation. He wrote this over a century before Francis Bacon's Novum Organum (1620), which is usually credited as founding empiricism. -D
On the Soul and the Body
What dwells within the flesh
Every part is disposed to unite with the whole, that it may thereby escape from its own incompleteness.
The soul desires to dwell with the body because without the members of that body it can neither act nor feel.
C.A. 59 r. b
Whoever would see in what state the soul dwells within the body, let him mark how this body uses its daily habitation, for if this be confused and without order the body will be kept in disorder and confusion by the soul.
C.A. 76 r. a
O thou that sleepest, what is sleep? Sleep is an image of death. Oh, why not let your work be such that after death you become an image of immortality; as in life you become when sleeping like unto the hapless dead.
C.A. 76 v. a
Man and the animals are merely a passage and channel for food, a tomb for other animals, a haven for the dead, giving life by the death of others, a coffer full of corruption.
C.A. 76 v. a
On Wisdom and Folly
Supreme happiness will be the greatest cause of misery, and the perfection of wisdom the occasion of folly.
C.A. 39 v. c
In youth acquire that which may requite you for the deprivations of old age; and if you are mindful that old age has wisdom for its food, you will so exert yourself in youth, that your old age will not lack sustenance.
C.A. 112 r. a
The air as soon as there is light is filled with innumerable images to which the eye serves as a magnet.
C.A. 109 v. a
This is where you hear Leonardo's voice most clearly — not the engineer or the anatomist, but the human being trying to make sense of his life and the world. Some of these passages are devastating in their honesty. -D