The labor which it would require to make a single one of these guns by hand would exhaust the patience and perseverance of any ordinary workman.
Innovation is not just about technology, but also about business models and ecosystems.
We are each our own devil, and we make this world our hell.
某个命题可以从某一组公理通过某一规则系统推导出来,这一事实本身并不使其为真。
The study of computational complexity is a journey through the landscape of mathematical logic and algorithmic theory.