光芒从一个山脊传到另一个山脊。
The world is full of people who have never, since childhood, met an open doorway with an open mind.
无畏并非毫无畏惧。它不是完全不害怕,而是心怀诸多恐惧却依然勇往直前。
Natural experiments are a powerful tool for understanding causal relationships in the real world.