I can't tell if I'm stupid if I'm joking.

Not being able to recognize other people's jokes is not necessarily stupid, but sometimes it may be for the following reasons:

1. Language understanding: Some people may not be sensitive to the literal meaning, which is what we often call "understanding".

2. Cultural background: People with different cultural backgrounds may have different understanding and acceptance of jokes.

3. Attention distribution: If a person's attention is focused on other things, or in a bad mood, he may not recognize other people's jokes.

4. Inferiority or inferiority: Some people may often fail to see their own advantages because of inferiority or inferiority. At this time, they may not recognize other people's jokes.

Therefore, not understanding other people's jokes does not necessarily mean being stupid, and it needs to be understood in combination with specific situations.