Sapere aude is the Latin phrase meaning “Dare to know”; and also is loosely translated as “Dare to be wise”, or even more loosely as "Dare to think for yourself!". Originally used in the First Book of Letters (20 BCE), by the Roman poet Horace, the phrase Sapere aude became associated with the Age of Enlightenment, during the 17th and 18th centuries, after Immanuel Kant used it in the essay, “Answering the Question: What Is Enlightenment?” (1784). As a philosopher, Kant claimed the phrase Sapere aude as the motto for the entire period of the Enlightenment, and used it to develop his theories of the application of Reason in the public sphere of human affairs.
In the 20th century, in the essay “What is Enlightenment?” (1984) Michel Foucault took up Kant's formulation of “dare to know” in an attempt to find a place for the individual man and woman in post-structuralist philosophy, and so come to terms with the problematic legacy of the Enlightenment. Moreover, in the essay The Baroque Episteme: the Word and the Thing (2013) Jean-Claude Vuillemin proposed that the Latin phrase Sapere aude be the motto of the Baroque episteme.
The phrase is widely used as a motto, especially by educational institutions.
The original use of the phrase Sapere aude appears in the First Book of Letters (20 BCE), by the Roman poet Horace; in the second letter, addressed to Lolius, in line 40, the passage is: Dimidium facti, qui coepit, habet; sapere aude, incipe. (“He who has begun is half done; dare to know; begin!”).
The phrase is the moral to a story, wherein a fool waits for a stream to cease flowing, before attempting to cross it. In saying, "He who begins is half done. Dare to know, dare to begin!", the Roman poet Horace suggests the value of human endeavour, of persistence in reaching a goal, of the need for effort to overcome obstacles. Moreover, the laconic Latin of Sapere aude also can be loosely translated as the English phrase “Dare to be wise”.