For an overview of the psychology of how people understand things (and don't!) I highly recommend this paper. It highlights a lot of ways our brains take shortcuts in terms of actually understanding things. And that facts play only one particular role amongst many other factors.
Keil, F. C. (2006). Explanation and understanding. Annu. Rev. Psychol., 57(1), 227-254. https://pmc.ncbi.nlm.nih.gov/articles/PMC3034737/pdf/nihms26...