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To write is to leave a legacy of thought.

"I hope that in this year to come, you make mistakes. Because if you are making mistakes, then you are making new things, trying new things, learning, living, pushing yourself, changing yourself, changing your world. You're doing things you've never done before, and more importantly, you're doing something."

Natural experiments are a powerful tool for understanding causal relationships in the real world.

我相信講故事的力量可以改變世界。