When ignorant people see someone who is dead, they are disgusted and horrified, even thought they too will be dead some day. I thought to myself: I don't want to be like the ignorant people. After then, I couldn't feel the usual intoxication with life anymore.
The thief steals from himself. The swindler swindles himself. For the real price is knowledge and virtue, whereof wealth and credit are signs. These signs, like paper money, may be counterfeited or stolen, but that which they represent, namely, knowledge and virtue, cannot be counterfeited or stolen.
It is commonly observed that a sudden wealth, like a prize drawn in a lottery or a large bequest to a poor family, does not permanently enrich. They have served no apprenticeship to wealth, and with the rapid wealth come rapid claims which they do not know how to deny, and the treasure is quickly dissipated.
Not to know what has been transacted in former times is to be always a child. If no use is made of the labors of past ages, the world must remain always in the infancy of knowledge.
To know how little one knows is to have genuine knowledge. Not to know how little one knows is to be deluded. Only those who know when they are deluded can free themselves from such delusion. The intelligent people are not deluded, because they know and accept their ignorance as ignorance, and thereby have genuine knowledge.
The science [geometry] is pursued for the sake of the knowledge of what eternally exists, and not of what comes for a moment into existence, and then perishes.