Whereas the beautiful is limited, the sublime is limitless, so that the mind in the presence of the sublime, attempting to imagine what it cannot, has pain in the failure but pleasure in contemplating the immensity of the attempt

Reason should investigate its own parameters before declaring its omniscience.

Beauty presents an indeterminate concept of Understanding, the sublime an indeterminate concept of Reason.

Laziness and cowardice explain why so many men. . . remain under a life-long tutelage and why it is so easy for some men to set themselves up as the guardians of all the rest. . . If I have a book which understands for me, a pastor who has a conscience for me, a doctor who decides my diet, I need not trouble myself. If I am willing to pay, I need not think. Others will do it for me.

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!

Act so that the maxim of your act could be made the principle of a universal law.

In every department of physical science there is only so much science, properly so-called, as there is mathematics.