Remember that set of thoughts on knowledge?
You know: there are things we know we don't know, "known unknowns."
And then there are the "unknown unknowns"… things we do NOT know that we lack in knowledge.
Over time, we learn more, and expand what theoretical physicist Marcelo Gleiser calls The Island of Knowledge.
His book by that name demonstrates how new scientific discoveries make many people uncomfortable, and actually expand ignorance.