随机实验是因果推理的黄金标准，但它们并不总是可行的。
"Randomized experiments are the gold standard for causal inference, but they are not always feasible."
I always try to push the boundaries of what can be done in film.
Policymakers should be open to revising their views based on new evidence.
If you want to fly, you have to give up the things that weigh you down.
