sapere aude

Etymology
lit. 'dare to know'. It is from the epithet of a parable, explaining that a fool waits for the stream to stop before crossing.

The original use seems to be in Epistle II of Horace's Epistularum liber primus :.

Phrase

 * 1) have the courage to think for yourself
 * 2) have courage to use your own reason,

Usage notes

 * Immanuel Kant described it as the motto of the Enlightenment in his essay "What Is Enlightenment?".
 * It is a frequently used motto for academic institutions.