“sapere aude.”

“Enlightenment is man's exodus from his self-incurred tutelage. Tutelage is the inability to use one's understanding without the guidance of another person..'Dare to Know'(sapere aude) Have the courage to use your own understanding;this is the motto of the Enlightenment.”

“Enlightenment is man's release from his self-incurred tutelage. Tutelage is man's inability to make use of his understanding without direction from another. Self-incurred is this tutelage when its cause lies not in lack of reason but in lack of resolution and courage to use it without direction from another. Sapere aude! 'Have courage to use your own reason!'- that is the motto of enlightenment.”

“Enlightenment is man's emergence from his self-imposed nonage. Nonage 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.”

“...new prejudices will serve as well as old ones to harness the great unthinking masses.For this enlightenment, however, nothing is required but freedom, and indeed the most harmless among all the things to which this term can properly be applied. It is the freedom to make public use of one's reason at every point. But I hear on all sides, 'Do not argue!' The Officer says: 'Do not argue but drill!' The tax collector: 'Do not argue but pay!' The cleric: 'Do not argue but believe!' Only one prince in the world says, 'Argue as much as you will, and about what you will, but obey!' Everywhere there is restriction on freedom.”

“Denken zonder ervaring is leeg, maar ervaring zonder denken is blind.”

“A categorical imperative would be one which represented an action as objectively necessary in itself, without reference to any other purpose.”