You can only know something if it is true. It could very well be that knowledge does not exist if nothing is true.
Thought Experiments
Knowledge Gathering
Grounding != Believing in Knowledge
Even if I know there might not be grounding in why I know something is true, I would still believe that I know it to be true. None of us are really skeptics about Causality, even if we can’t prove causation.
Knowledge Inheritance Cycle
If I say I know this because my mom knows this, how does my mom know this?