"Life well spent is long."

"The greatest pleasure and the greatest knowledge is to understand how we are born."

"He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast."

"The memory of all that is past is as nothing in comparison with the knowledge of what is to come."

"The soul desires to dwell with the body, because without the corporeal instruments, it can neither act nor feel."