In Japan, being introduced to someone through a mutual friend can lower your guard considerably compared with meeting a complete stranger on your own.
The reason is simple. Some of the trust you already have in your friend can carry over to the new person. You may naturally think, “If my friend is introducing us, this is probably not someone I need to be especially wary of.”
This is not a uniquely Japanese reaction. People in many countries are more likely to trust someone who comes recommended by a person they already know. It would therefore be misleading to say that Japanese people cannot trust someone without an introduction.
Still, in situations where introductions matter in Japan, the existing relationship itself—who knows whom—can become part of the information used to judge a new person.
One reason is that the person making the introduction may feel a small degree of responsibility for what happens afterward.
Suppose you introduce friend A to friend B, and A later behaves very rudely toward B. A is clearly the person at fault. Even so, you may still feel awkward and think, “I’m sorry I introduced someone like that,” or “I feel bad for B.”
In other words, when you introduce someone, a little of your own reputation goes with them.
That is also why the person being introduced may feel more comfortable. The introducer is not guaranteeing the other person’s character or background. Even so, the fact that someone they trust was willing to connect the two can serve as a small piece of reassuring information.
Introductions can matter in Japan not because introducing people is some special ritual, but because trust that already exists in one relationship can be carried into the beginning of another. It also works because the person making the introduction may feel that what happens afterward reflects on them, at least to some extent.
