... mathematical knowledge ... is, in fact, merely verbal knowledge. "3" means "2+1", and "4" means "3+1". Hence it follows (though the proof is long) that "4" means the same as "2+2". Thus mathematical knowledge ceases to be mysterious.

Science may set limits to knowledge, but should not set limits to imagination.

In his youth, Wordsworth sympathized with the French Revolution, went to France, wrote good poetry and had a natural daughter. At this period, he was a bad man. Then he became good, abandoned his daughter, adopted correct principles and wrote bad poetry.

With equal passion I have sought knowledge. I have wished to understand the hearts of men. I have wished to know why the stars shine. And I have tried to apprehend the Pythagorean power by which number holds sway about the flux. A little of this, but not much, I have achieved.

The problem with the wise is they are so filled with doubts while the dull are so certain.

Every increase in knowledge requires an increase in wisdom

The world is full of magical things patiently waiting for our wits to grow sharper.