Lukasiewicz also studied Aristotelian, Stoic and other nonmodern logics. One of his early
works is On Aristotle's Principle of Contradiction. Due to such studies, Lukasiewicz had a better
sense of the history of logic than, say, Bertrand Russell did.

In addition to his three-valued logic, Lukasiewicz developed an infinite-valued logic, with
truth values on the reals from (false) to 1 (true). No, this did
not originate with Lotfi Zadeh. Zadeh's first paper on fuzzy set theory has a footnote
indicating that his theory comes from a modification of Lukasiewicz's.