Enlightenment is man's exodus from his self-incurred tutelage. Tutelage is the inability to use one's understanding without the guidance of another p… - Immanuel Kant

To know what questions may reasonably be asked is already a great and necessary proof of sagacity and insight. For if a question is absurd in itself and calls for unnecessary answers, it not only brings disgrace to the person raising it, but may prompt an incautious listener to give absurd answers, thus presenting, as the ancients said, the laughable spectacle of one person milking a he-goat, and another holding the sieve underneath.

A great part, perhaps the greatest part, of the business of our reason consists in the analysation of the conceptions which we already possess of objects.

Space and time are the framework within which the mind is constrained to construct its experience of reality.