The essence of cryptography is to allow communication in the presence of adversaries.

No man, for any considerable period, can wear one face to himself and another to the multitude, without finally getting bewildered as to which may be the true.

今天很残酷，明天更残酷，后天很美好，但绝大部分人死在明天晚上。

怀疑是智慧的开端。