改变行为的唯一方法是通过操纵强化偶然性。
The only way to change behavior is through manipulation of reinforcement contingencies.
A vision without action is merely a dream.
Leadership means making tough decisions today for a better tomorrow.
Science is not about being right; it's about being less wrong.
The historian’s task is to bring the dead to life.
世界就在你面前,你不必接受它或离开它,就像你进来时那样。