Gert Lokhorst lists Mally's 35 theorems and gives a proof for Menger's theorem at the Stanford Encyclopedia of Philosophy under Mally's Deontic Logic. The first plausible system of deontic logic was proposed by G. H. von Wright in his paper Deontic Logic in the philosophical journal Mind in 1951.

Who founded logic?

Aristotle is considered the founder of logic as he was the first philosopher to systematically organize logic in his volume on the subject.

What is Deontic reasoning?

Deontic reasoning is thinking about whether actions are forbidden or allowed, obligatory or not obligatory.