The Literary Works of Leonardo da Vinci, Vol. I — Prolegomena and the Treatise on Painting (Richter §1–720)notebook · notebooks c. 1478–1518; trans. 1883DirectVerified quotation — claim 01“The eye, which is called the window of the soul, is the principal means by which the central sense can most completely and abundantly appreciate the infinite works of nature.” — Leonardo da Vinci · trans. Jean Paul Richter, 1883
Sources supporting claim 01
The Literary Works of Leonardo da Vinci, Vol. II — Philosophical Maxims, Morals and Polemics (Richter §1149–1202)notebook · notebooks c. 1490–1518; trans. 1883DirectVerified quotation — claim 01“Any one who in discussion relies upon authority uses, not his understanding, but rather his memory.” — Leonardo da Vinci · trans. Jean Paul Richter, 1883