If anyone ever tells you, “you’re stupid”, don’t believe them.
They have no idea what they’re talking about.
Let me explain to you what’s really going on when something like this happens:
Clearly, there was something you didn’t know and the person who called you “stupid” was frustrated by your failure to meet their personal expectations.
Instead of dealing with their own frustrations in a responsible, mature, and respectful manner, they decided to attack your intelligence with degrading speech.
In short, they projected their unresolved angst upon you and chose to treat their problem as if it were your shortcoming.
Don’t take ownership of their unresolved angst.
No one is stupid.
We’re all uninformed relative to some things and we’re all immensely knowledgeable relative to other things.
Being uninformed about something, however obvious or important it is to everyone else, does not make you an idiot.
You are not stupid.
Immediately dismiss anyone who is ignorant enough to ever tell you that you are.