Apagogue
The apagogue (from ancient Greek ἀπαγωγή apagōgē , German 'Ab-, Wegführung ' ), also called abduction or Latin abductio , is a conclusion from a known, true major proposition and a credible, but uncertain minor proposition to a conclusion according to the rules of syllogistics . (Cf. Aristotle , Analytica priora , II 25). The sub-clause should be plausible, but at least more plausible than the desired conclusion itself. According to Aristotle, the plausibility of the sub-clause can be shown by the fact that the connection between the middle and sub-concept only needs a few mediating terms. If it is possible to link the superordinate and subordinate concepts to other and less mediating concepts, i.e. omitting the proposed sub-clause, then according to Aristotle it is not an apagogue.
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| In his example, Aristotle regards an apagogue with “teachability” as a generic term and “justice” as a sub-term. For the apagogue, “knowledge” is chosen as the middle term. Thus, “all knowledge is teachable” is formed as a major principle , which is considered true. The sub-clause then results in “ Justice is a knowledge ”, and the conclusion: “ Justice is teachable ”. This is an apagogue that combines justice and teachability. It can be strengthened if justice is understood, for example, as knowledge of the correct proportions in the distribution of goods, because then the minor premise is fulfilled. |
The term apagogical proof , Latin demonstratio apagogica , is derived from this , better known as reductio ad absurdum or indirect proof; A major premise is proven if a counterexample or a general contradiction can be derived from its negation.
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| We want to prove that knowledge can be taught. Let us assume the negation of this thesis: " Knowledge is not teachable ". Let us further assume that we knew that justice can be taught (our conclusion above). If the sentence “Justice is a knowledge” is true, the example of justice refutes that knowledge cannot be taught, and thus the thesis is proven. Here, too, the credibility of "Justice is a knowledge" is important . |
Recovery by CS Peirce
Charles Sanders Peirce takes up the apagogue again, but by his “abduction” he understands above all the logic of the discovery of minor points.
See also
literature
- Johannes Hoffmeister, Philosophical Dictionary , Verlag Felix Meiner, Hamburg, 1955
- Aristotle, First Analytics , translation by Julius von Kirchmann , 1876. (The digital library, philosophy from Plato to Nietzsche, p. 2767)
Web links
Individual evidence
- ^ Wilhelm Gemoll : Greek-German school and hand dictionary . G. Freytag Verlag / Hölder-Pichler-Tempsky, Munich / Vienna 1965.
- ^ Rudolf Eisler : Dictionary of Philosophical Terms. 1904, accessed February 8, 2011 .