过去是你记得的、你想象你记得的、你确信你记得的、或者你假装记得的。
The past is what you remember, imagine you remember, convince yourself you remember, or pretend you remember.
In computational complexity, we are not just dealing with the limits of what we can compute, but also with the limits of what we can prove.
最大的风险就是不冒任何风险。在这个快速变化的世界里，唯一注定失败的策略就是不冒险。