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The world has the technology - either available or well advanced in the research pipeline - to feed on a sustainable basis a population of 10 billion people.

讀書的時候不要只想作者怎么看，想想你自己怎么看。

數學不是關于數字、方程、計算或算法：它是關于理解的。

Without a good user experience, even the best business model is just talk.

"The best way to learn is by making mistakes."