阅读下面短文，按要求完成下列各题。

Socrates was famous in ancient Greece for his knowledge. One day, one of his friends went up to him and said, “I’ve just heard something about your friend, do you want to know?”

“Well,” Socrates said, “Before telling me anything, I’d like you to pass a test. It’s called the triple filter (三重筛选) test.”

“Triple filter?”

“That’s right,” Socrates continued, “Before you talk to me about my friend, it is a good idea to think about what you will say. The first filter is ________. Are you sure what you are going to tell me is true?”

“In fact, I just heard about it and…” the man said.

“All right,” Socrates said, “So you don’t really know whether it’s true or not. Now let’s try the second filter—goodness. Is what you are going to tell me good?”

“No, on the contrary (相反)…” the man replied.

“Okay,” Socrates continued, “The last filter is usefulness. Is what you are going to tell me useful to me?”

“No, not really.” The man said.

“Well,” Socrates ended, “If what you want to tell me is not true, good or even useful, why tell it to me at all?”

（1）Why did the man go up to Socrates one day? (根据短文内容回答问题)

_________________________________________________

（2）How many questions did Socrates ask the man? (根据短文内容回答问题)

_________________________________________________

（3）According to the story, what do you think of Socrates? (根据短文内容回答问题)

_________________________________________________

（4）根据短文内容，给下面的句子补充一个单词，使句子意思完整。

The first filter is ________.

（5）根据短文内容，完成句子。

This story teaches us ________________________________.