ABSTRACT
The THOG problem was first reported by Peter Wason in 1977, though it was apparently devised a year earlier than this. Wason (1977) claims that one of his principal reasons for devising the problem was that the selection task was becoming too well known and that he wanted another way of looking at people’s self-contradictions. It is interesting to note in this light that the selection task has since generated a vast literature and is now arguably the single most popular paradigm in the study of human reasoning, while the THOG problem remains much less well known and less widely researched. Nevertheless, we will argue here that it can provide important insights into the cognitive processes involved in reasoning.
