我们必须停止空谈改变,开始行动。
在弦理论的景观中,可能有10^500种不同的真空状态,每种状态对应一个不同的可能宇宙。
What we learn from history is that people don't learn from history.
It seems to me that if you or I must choose between two courses of thought or action, we should remember our dying and try so to live that our death brings no pleasure to the world.