Learning never exhausts the mind.
Leonardo da Vinci
I love those who can smile in trouble, who can gather strength from distress, and grow brave by reflection. 'Tis the business of little minds to shrink, but they whose heart is firm, and whose conscience approves their conduct, will pursue their principles unto death.
The greatest deception men suffer is from their own opinions.
Poor is the pupil who does not surpass his master.
Art is never finished, only abandoned.
The noblest pleasure is the joy of understanding.
There are three classes of people: those who see, those who see when they are shown, those who do not see.
A beautiful body perishes, but a work of art dies not.
Tears come from the heart and not from the brain.
Nature is the source of all true knowledge. She has her own logic, her own laws, she has no effect without cause nor invention without necessity.
I have been impressed with the urgency of doing. Knowing is not enough; we must apply. Being willing is not enough; we must do.
Nothing strengthens authority so much as silence.
Water is the driving force of all nature.
The human foot is a masterpiece of engineering and a work of art.
While I thought that I was learning how to live, I have been learning how to die.
As a well-spent day brings happy sleep, so a life well spent brings happy death.
Iron rusts from disuse; water loses its purity from stagnation... even so does inaction sap the vigor of the mind.
Where the spirit does not work with the hand, there is no art.
Why does the eye see a thing more clearly in dreams than the imagination when awake?
Our life is made by the death of others.
Where there is shouting, there is no true knowledge.
In rivers, the water that you touch is the last of what has passed and the first of that which comes; so with present time.
He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.
Time abides long enough for those who make use of it.
The smallest feline is a masterpiece.
It's easier to resist at the beginning than at the end.
Time stays long enough for anyone who will use it.
Blinding ignorance does mislead us. O! Wretched mortals, open your eyes!
I have offended God and mankind because my work didn't reach the quality it should have.
All our knowledge has its origins in our perceptions.
The beginnings and ends of shadow lie between the light and darkness and may be infinitely diminished and infinitely increased. Shadow is the means by which bodies display their form. The forms of bodies could not be understood in detail but for shadow.
Who sows virtue reaps honor.
You can have no dominion greater or less than that over yourself.
Marriage is like putting your hand into a bag of snakes in the hope of pulling out an eel.
The natural desire of good men is knowledge.
Life well spent is long.
Anyone who conducts an argument by appealing to authority is not using his intelligence; he is just using his memory.
Nature never breaks her own laws.
Men of lofty genius when they are doing the least work are most active.
Just as courage imperils life, fear protects it.
Human subtlety will never devise an invention more beautiful, more simple or more direct than does nature because in her inventions nothing is lacking, and nothing is superfluous.
He who is fixed to a star does not change his mind.
He who wishes to be rich in a day will be hanged in a year.
You do ill if you praise, but worse if you censure, what you do not understand.
The human bird shall take his first flight, filling the world with amazement, all writings with his fame, and bringing eternal glory to the nest whence he sprang.
Beyond a doubt truth bears the same relation to falsehood as light to darkness.
As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.
The function of muscle is to pull and not to push, except in the case of the genitals and the tongue.
Intellectual passion drives out sensuality.
Medicine is the restoration of discordant elements; sickness is the discord of the elements infused into the living body.