By Walter Isaacson

• Leonardo’s genius was based on skills we can aspire to improve in ourselves, such as curiosity and intense observation. He had imagination so excitable that it flirted with the edges of fantasy...His ability to blur the line between reality and fantasy was a key to his creativity...Leonardo knew how to marry observation and imagination, which made him history’s consummate innovator.
• “the most relentlessly curious man in history”
• His ability to combine art, science, technology, the humanities, and imagination remains an enduring recipe for creativity.
• “They will say that because I have no book learning I cannot properly express what I desire to describe - but they do not know that my subjects require experience rather than the words of others.”
• His method was rooted in experiment, curiosity, and the ability to marvel at phenomena that the rest of us rarely pause to ponder after we’ve outgrown our wonder years.
• Florence’s festive culture was spiced by the ability to inspire those with creative minds to combine ideas from disparate disciplines...The culture rewarded, above all, those who mastered and mixed different disciplines.
• “Unlike other painters, Leonardo took care to render the blood dripping from the fish’s cut belly.”
• “It seemed to him that the hand was not able to attain to the perfection of art in carrying out the things which he imagined.”
• Leonardo clung to his favorite works, carried them with him when he moved, and returned to them when he had new ideas.
• By the end of his career, his pursuits of how the brain and nerves turned emotions into motions became almost obsessive. It was enough to make the Mona Lisa smile.
• As with so many other of Leonardo’s visionary designs, he was ahead of what was practical for his time. Ludovico did not adopt his vision of the city, but in this case Leonardo’s proposals were sensible as well as brilliant. If even part of his plan had been implemented, it might have transformed the nature of cities, reduced the onslaught of plagues, and changed history.
• His creativity came from his combinatory imagination.
• His musical pursuits launched him onto more substantive paths: they laid the ground for his work on the science of percussion - how striking an object can produce vibrations, waves, reverberations - and exploring the analogy between sound waves and water waves.
• He would walk the streets with a notebook dangling from his belt, find a group of people with exaggerated features who would make good models, and invite them over for supper. ”Sitting close to them, Leonardo then proceeded to tell the maddest and most ridiculous tales imaginable, making them laugh uproariously. He observed all their gestures very attentively and those ridiculous things they were doing, and impressed them on his mind; and after they had left, he retired to his room and there made a perfect drawing.”
• He was not motivated by wealth or material possessions. In his notebooks, he decried “men who desire nothing but material riches and are absolutely devoid of the desire for wisdom, which is the sustenance and truly dependable wealth of the mind.”
• Leonardo wrote in one of his drawings “Pleasure and Pain are represented as twins because there is never one without the other.”
• “Though I have no power to quote from authors as they have, I shall rely on a far more worthy thing - on experience.”
• He would try and look at facts and from them figure out the patterns and natural forces that caused those things to happen.