angels dancing on the head of a pin

Meaning

Noun

• The subject of arcane intellectual speculation; used as an example subject of enquiry the pursuit of which is of no value.

Origin

• An allusion to the theological question “How many angels can dance on the head of a pin?” — a question cited to debunk mediaeval angelology in particular and scholasticism in general. The point is that explorative discussions that the discussants consider important can be academic in both senses of that word—not only arcane but also irrelevant.