Those who fall in love with practice without science are like a sailor who enters a ship without a helm or a compass, and who never can be certain whither he is going.
 Leonardo da Vinci, The Notebooks of Leonardo Da Vinci (1478 – 1519). copy citation

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Author Leonardo da Vinci
Source The Notebooks of Leonardo Da Vinci
Topic science love
Date 1478 – 1519
Language English
Reference
Note Translated by Jean Paul Richter in 1888
Weblink http://www.gutenberg.org/cache/epub/5000/pg5000-images.html

Context

“and since the cause is more to be praised than the effect, I will rather praise a good disposition without culture, than good culture without the disposition. 1160. Science is the captain, and practice the soldiers. 1161. OF THE ERRORS OF THOSE WHO DEPEND ON PRACTICE WITHOUT SCIENCE. Those who fall in love with practice without science are like a sailor who enters a ship without a helm or a compass, and who never can be certain whither he is going. II. MORALS. What is life? (1162. 1163) . 1162. Now you see that the hope and the desire of returning home and to one's former state is like the moth to the light, and that the man who with constant longing awaits with joy each new spring time, each new summer, each new month and new year—deeming that the things he longs for are ever too late in coming—does not perceive that he is longing for his own destruction.” source