One can't proceed from the informal to the formal by formal means.
现代密码学的挑战不仅在于保护信息,而且在于以一种既高效又可扩展的方式来实现。
没有丑陋的爱,也没有英俊的监狱。
Survival is not about being fearless. It's about making a decision, getting on and doing it, because you have to.