The only purpose for which power can be rightfully exercised over any member of a civilized community， against his will， is to prevent harm to others.

Fear is the enemy of freedom.

可持续性必须有利可图，否则它就无法持续。

The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants.

In mathematics, truth is always relative to the system you're working in.

写作是对世界和自我的见证。