I don't know
There’s no shame in not knowing. I observe there are people who hate to admit their lack of knowledge about certain things. Sometimes myself included.
But I don’t buy into the idea that one should know everything. There have been plenty of times when I’ve been hit with questions I couldn’t answer, and I just replied, “I don’t know”. Not knowing doesn’t mean you’re foolish.
There’s just always somebody who’s smarter. Someone who knows something better than us. Someone who’s got an angle at something we haven’t figured out yet. And you know what? That’s perfectly fine. There is no monopoly of knowledge.
We don’t need to pretend we have it all down. There’s something freeing in saying “I don’t know” because it opens the door to learning. And only from the acceptance of what we lack can we gain the opportunity to grow.