What do I know? And what do you?
When my daughter was around six, I was her hero. She was sure I knew all the knowable. When she once told me that I knew everything, we were at dinner, and the tablecloth was a checkered one, a yarn-dyed fabric with a texture of cotton threads. I pointed a square with my finger and told her that this was what humanity knew. Then I narrowed it down to the smallest fiber in it and said it was even too big to represent my knowledge. At that point, the tablecloth was what I and humanity don't know.
That day I lost my biggest fan, maybe, but I was finally free from impostor syndrome.
And you? What is your tiny fiber or thread of knowledge?
Against the universe of the infinite tablecloth, you and I are just enormously ignorant.