Ernst Mally
Ernst Mally | |
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Born | 11 October 1879 |
Institutions | University of Graz (1925–1942) |
Theses | |
Nuclear vs. extranuclear (formal vs. extra-formal) properties (formale vs. außerformale Bestimmungen) of objects[5][6][7] )Abstract determinates (Determinaten) as the content of mental states[4][3] Axiomatization of ethics (deontic logic |
Ernst Mally (
Life
Mally was born in the town of
In 1898, he enrolled in the
From 1915 to 1918 he served as an officer in the
He died in 1944 in
Philosophical work
Mally's deontic logic
Mally was the first logician ever to attempt an
Note the implied
The fourth axiom has confused some logicians because its formulation is not as they would have expected, since Mally gave each axiom a description in words also, and he said that axiom IV meant "the unconditionally obligatory is obligatory", i.e. (as many logicians have insisted) UA → !A. Meanwhile, axiom 5 lacks an object to which the predicates apply, a
Failure of Mally's deontic logic
Theorem: This axiomatization of deontic logic implies that !x if and only if x is true, OR !x is unsatisfiable. (This makes it useless to deontic logicians.) Proof: Using axiom III, axiom I may be rewritten as (!(A → B) & (B → C)) → !(A → C). Since B → C holds whenever C holds, one immediate consequence is that (!(A → B) → (C → !(A → C))). In other words, if A requires B, it requires any true statement. In the special case where A is a tautology, the theorem has consequence (!B → (C → !C)). Thus, if at least one statement ought be true, every statement must materially entail it ought be true, and so every true statement ought be true. As for the converse (i.e. if some statement ought be true then all statements that ought be true are true), consider the following logic: ((U → !A) & (A → ∩)) → (U → !∩) is a special case of axiom I, but its consequent contradicts axiom V, and so ¬((U → !A) & (A → ∩)). 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. The theorem above, however, would then not be demonstrable. The theorem was proven by Karl Menger, the next deontic logician. Neither Mally's original axioms nor a modification that avoids this result remains popular today. Menger did not suggest his own axioms. (See also deontic logic for more on the subsequent development of this subject.)
Metaphysics
In
Mally developed a
Legacy
Mally's metaphysical work influences some contemporary metaphysicians and logicians working in
The analytic philosopher
Works
- (1904 [1903]) Untersuchungen zur Gegenstandstheorie des Messens (Investigations in the Object Theory of Measurement), Leipzig: Barth (doctoral thesis).
- (1912) Gegenstandstheoretische Grundlagen der Logik und Logistik (Object-theoretic Foundations for Logics and Logistics), Leipzig: Barth (habilitation thesis).
- (1926) Grundgesetze des Sollens. Elemente der Logik des Willens (The Basic Laws of Ought: Elements of the Logic of Willing), Graz: Leuschner & Lubensky. Reprinted in Ernst Mally: Logische Schriften. Großes Logikfragment—Grundgesetze des Sollens, K. Wolf, P. Weingartner (eds.), Dordrecht: Reidel, 1971, 227–324.
- (1935) Erlebnis und Wirklichkeit. Einleitung zur Philosophie der Natürlichen Weltauffassung (Experience and Reality: Introduction to the Philosophy of the Natural World-conception), Leipzig: Julius Klinkhardt.
Notes
- ^ a b Liliana Albertazzi, Dale Jacquette, The School of Alexius Meinong, Routledge, 2017, p. 191.
- ^ a b c d e Hieke & Zecha
- ^ a b c Edward N. Zalta, "Mally's Determinates and Husserl's Noemata", in Ernst Mally – Versuch einer Neubewertung, A. Hieke (ed.), St. Augustin: Academia-Verlag, 1998, pp. 9–28.
- ^ a b Mally 1912, §§33 and 39.
- International Congress of Philosophy, Heidelberg), 1–5 September 1908; ed. Professor Dr. Theodor Elsenhans, 881–886. Heidelberg: Carl Winter’s Universitätsbuchhandlung. Verlag-Nummer 850. Translation: Ernst Mally, "Object Theory and Mathematics", in: Jacquette, D., Alexius Meinong, The Shepherd of Non-Being (Berlin/Heidelberg: Springer, 2015), pp. 396–404, esp. 397.
- ^ Dale Jacquette, Meinongian Logic: The Semantics of Existence and Nonexistence, Walter de Gruyter, 1996, p. 16.
- ^ a b c Ernst Mally – The Metaphysics Research Lab
- ^ a b Mally 1912, ch. I. "Allgemeines".
- ^ Zalta, Edward. "The Theory of Abstract Objects". Metaphysics Research Lab. Retrieved 5 September 2020.
- ^ Lewis, David. "Ern Malley's Namesake" (PDF). Quadrant (March 1995): 14–15. Retrieved 5 September 2020.
References
- Hieke, Alexander; Zecha, Gerhard. "Ernst Mally". In Zalta, Edward N. (ed.). Stanford Encyclopedia of Philosophy.
- Lokhorst, Gert-Jan. "Mally's Deontic Logic". In Zalta, Edward N. (ed.). Stanford Encyclopedia of Philosophy.