The only way to change behavior is through manipulation of reinforcement contingencies.
人生之要事在于确立伟大的目标与实现这目标的决心。
当准备遇到机会时,成功就会到来。
统一自然界所有力的挑战是几十年来推动理论物理学发展的动力之一。
To live remains an art which everyone must learn,and which no one can teach.