This fear actually proceeds from an even deeper impulse, the belief that quick judgment thinking (what I call memetic epistemology) is superior to extrinsic thinking.
They trust their instincts more than any other person, regardless of their expertise.
Conservatives and reactionaries believe that their views are true because 𝒕𝒉𝒆𝒚 believe them. Evidence isn't needed for "common sense."
This viewpoint is the fundamental unifier of everyone on the right, from atheist ancaps to Christofascists.