>Nonage [immaturity] is the inability to use one’s own understanding without another’s guidance. This nonage is self-imposed if its cause lies not in lack of understanding but in indecision and lack of courage to use one’s own mind without another’s guidance. Dare to know! (*Sapere aude*) 'Have the courage to use your own understanding,' is therefore the motto of the Enlightenment.
"What is Enlightenment" wikipedia