Illicit Substitution Of Identicals

A formal fallacy due to confusing the knowing of a thing (extension ) with the knowing of it under all its various names or descriptions (intension ). We need to define two terms here to understand this fallacy fully: intensional and extensional .

Examples:

  • _The lady in the pink dress is Julia Roberts.

The reporter thinks the lady in the pink dress drives a Prius.

Therefore, the reporter thinks Julia Roberts drives a Prius ._

Synonyms: hooded man fallacy, masked man fallacy, intensional fallacy