I don't know that I have a pancreas, spleen, or heart.
I've never bothered to check.
I don't know if they're even real.
I've never seen one.
I don't know what an atom looks like.
I'm not that small.
I don't think that it's very plausible for DNA to exist.
Because I've never held it.
What do I know?
I know that the things I know aren't the limits.