The best weapon of a dictatorship is secrecy, but the best weapon of a democracy should be the weapon of openness.

The more determinedly I exist, as myself, within the conditions of the time, the more clearly I shall hear the language of the past, the nearer I shall feel the breath of the centuries.

蒸汽机是改善人类状况的最有力工具。

密码学的目标是使破解系统的成本超过受保护信息的价值。