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Primary sourceBook16th century (published 1904)

Thoughts

Leonardo da Vinci · 16th century (published 1904)

A collection of Leonardo da Vinci's own aphorisms and reflections on science, theory, and practice.

These are Leonardo's own private reflections on science and practice, straight from his notebooks.

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About this source

What it is

These are short written thoughts and aphorisms by Leonardo da Vinci, recorded in his notebooks during the 16th century and later edited by Edmondo Solmi, published in Florence in 1904.

Why it matters

In these reflections, Leonardo argues that theory must come before practice—comparing science to a captain and practice to soldiers who follow. This offers direct insight into how Leonardo thought about the relationship between knowledge and skill, especially in painting and perspective, revealing the intellectual framework behind his artistic and scientific work.

Look closer

  • What does Leonardo mean when he compares a painter without scientific knowledge to someone looking in a mirror?
  • Why might Leonardo have insisted that theory come before practice?
  • How might these private notebook thoughts differ from something written for an audience?

This book is part of the curated material that grounds the AI version of Leonardo da Vinci on Humy.ai — when students ask about related events, the AI can quote it and cite it.

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