The wisdom of Leonardo da Vinci.

• Art is never finished, only abandoned.
• As a well-spent day brings happy sleep, so a life well spent brings happy death.
• As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.
• Beyond a doubt truth bears the same relation to falsehood as light to darkness.
• Blinding ignorance does mislead us. O! Wretched mortals, open your eyes!
• Common Sense is that which judges the things given to it by other senses.
• For once you have tasted flight you will walk the earth with your eyes turned skywards, for there you have been and there you will long to return.
• 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.
• He who wishes to be rich in a day will be hanged in a year.
• I have been impressed with the urgency of doing. Knowing is not enough; we must apply. Being willing is not enough; we must do.
• 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.
• Iron rusts from disuse; water loses its purity from stagnation... even so does inaction sap the vigour of the mind.
• It had long since come to my attention that people of accomplishment rarely sat back and let things happen to them. They went out and happened to things.
• It's easier to resist at the beginning than at the end.
• Just as courage imperils life, fear protects it.
• Learning never exhausts the mind.
• Nature never breaks her own laws.
• Nothing strengthens authority so much as silence.
• Our life is made by the death of others.
• Simplicity is the ultimate sophistication.
• The greatest deception men suffer is from their own opinions.
• The noblest pleasure is the joy of understanding.
• The smallest feline is a masterpiece.
• The truth of things is the chief nutriment of superior intellects.
• There are three classes of people: those who see, those who see when they are shown, those who do not see.
• Time stays long enough for anyone who will use it.
• Water is the driving force of all nature.
• Where the spirit does not work with the hand, there is no art.
• Where there is shouting, there is no true knowledge.
• Who sows virtue reaps honor.
• You can have no dominion greater or less than that over yourself.
• You do ill if you praise, but worse if you censure, what you do not understand.