Ernst Mally (/ˈmɑːli/; German: [ˈmali]; 11 October 1879 – 8 March 1944) was an Austrian analytic philosopher,[2][3] initially affiliated with Alexius Meinong's Graz School of object theory.
Mally was one of the founders of deontic logic and is mainly known for his contributions in that field of research.
[7] Mally was born in the town of Kranj (German: Krainburg) in the Duchy of Carniola, Austria-Hungary (now in Slovenia).
His father was of Slovene origin, but identified himself with Austrian German culture (he also Germanized the orthography of his surname, originally spelled Mali, a common Slovene surname of Upper Carniola).
After his death, the family moved to the Carniolan capital of Ljubljana (German: Laibach).
Already at a young age, Mally became a fervent supporter of the Pan-German nationalist movement of Georg von Schönerer.
In 1898, he enrolled in the University of Graz, where he studied philosophy under the supervision of Alexius Meinong, as well as physics and mathematics, specializing in formal logic.
He graduated in 1903 with a doctoral thesis entitled Untersuchungen zur Gegenstandstheorie des Messens (Investigations in the Object Theory of Measurement).
In 1906 he started teaching at a high school in Graz, at the same time collaborating with Adalbert Meingast and working as Meinong's assistant at the university.
He also maintained close contacts with the Graz Psychological Institute, founded by Meinong.
In 1912, he wrote his habilitation thesis entitled Gegenstandstheoretische Grundlagen der Logik und Logistik (Object-theoretic Foundations for Logics and Logistics) at Graz with Meinong as supervisor.
In 1938, he became a member of the National Socialist Teachers League and two months after the Anschluss he joined the NSDAP.
They form a first-order theory that quantifies over propositions, and there are several predicates to understand first.
Theorem: This axiomatization of deontic logic implies that !x if and only if x is true, OR !x is unsatisfiable.
The result !A → A can be shown to follow from this, since !A implies that U → !A and ¬A implies that A → ∩; and, since these are not both true, we know that !A → A. Mally thought that axiom I was self-evident, but he likely confused it with an alternative in which the implication B → C is logical, which would indeed make the axiom self-evident.
Neither Mally's original axioms nor a modification that avoids this result remains popular today.
In metaphysics, Mally is known for introducing a distinction between two kinds of predication, a strategy better known as the dual predication approach, for solving the problem of nonexistent objects (Mally 1912).
[9] The analytic philosopher David Kellogg Lewis argued forcefully that the name of the fictional Australian poet Ern Malley, created by James McAuley and Harold Stewart, was an allusion to Mally.