Observation is always selective. It needs a chosen object, a definite task, an interest, a point of view, a problem.

Observation is always selective. It needs a chosen object, a definite task, an interest, a point of view, a problem.

观察总是有选择性的。它需要一个选定的对象，一个明确的任务，一个兴趣，一个观点，一个问题。

-- Karl Popper 波普尔