Science is the observation of things possible, whether present or past; prescience is the knowledge of things which may come to pass, though but slowly.
 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 observation science
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

“To know and to will are two operations of the human mind.
Discerning, judging, deliberating are acts of the human mind.
1147.
All our knowledge has its origin in our preceptions.
Science, its principles and rules (1148—1161)
1148.
Science is the observation of things possible, whether present or past; prescience is the knowledge of things which may come to pass, though but slowly. 1149.
Experience, the interpreter between formative nature and the human race, teaches how that nature acts among mortals; and being constrained by necessity cannot act otherwise than as reason, which is its helm, requires her to act.
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