The Liskov Substitution Principle is a fundamental concept in object-oriented programming, stating that objects of a superclass should be replaceable with objects of a subclass without affecting the correctness of the program.

I think the key to directing is to be open to change.

Tradition is important, but evolution is necessary.

农业效率绝不能以牺牲环境管理为代价。

如果生者不让死者安息，死者就不会安息。

一无所有只能换来一无所有。