Why does hiding the threat (darkness, obscurity, withheld information) make horror scarier, and is that measured or craft lore?

Three openly readable craft texts (Burke 1757, Radcliffe 1826, Lovecraft) argue that fear rests on the unseen or the unknown, and Radcliffe adds a useful limit: obscurity must leave the imagination something to work with, while confusion does not. The only measured support found is indirect: a non-film shock-learning experiment where stress responses peaked at maximal uncertainty. No open-access study was found that tests darkness or monster-reveal timing in a film, so those claims remain craft lore. Curator qualifications: All excerpts located; Radcliffe terror/horror vs Lovecraft vocabulary mismatch kept. Rights: PD status assumed (hold per FB43). Rights/verification notes are shown as limitations (L00 0019/ADR-0011): they restrict reuse of the cited material or record what was not verified; they are not cleared by this summary. Limitations: [verification_limitation] Radcliffe/Lovecraft page status assumed (hold). Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://www.gutenberg.org/cache/epub/15043/pg15043.txt",
      "note": "candidate evidence excerpts"
    },
    {
      "url": "https://sites.ualberta.ca/~dmiall/Novel/Radcliffe_supernatural.htm",
      "note": "candidate evidence excerpts"
    },
    {
      "url": "https://www.hplovecraft.com/writings/texts/essays/shil.aspx",
      "note": "candidate evidence excerpts"
    },
    {
      "url": "https://www.nature.com/articles/ncomms10996",
      "note": "candidate evidence excerpts"
    }
  ]
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