A man who is mounting any slope finds that he must involuntarily throw the most weight forward, on the higher foot, rather than behind—that is in front of the axis and not behind it. Hence a man will always, involuntarily, throw the greater weight towards the point whither he desires to move than in any other direction.
 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 desire axis
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

“369. A sitting man cannot raise himself if that part of his body which is front of his axis [centre of gravity] does not weigh more than that which is behind that axis [or centre] without using his arms. A man who is mounting any slope finds that he must involuntarily throw the most weight forward, on the higher foot, rather than behind—that is in front of the axis and not behind it. Hence a man will always, involuntarily, throw the greater weight towards the point whither he desires to move than in any other direction. The faster a man runs, the more he leans forward towards the point he runs to and throws more weight in front of his axis than behind. A man who runs down hill throws the axis onto his heels, and one who runs up hill throws it into the points of his feet;” source