Petitio Principii

A Petitio Principii (from Latin Petitio principii , for "claiming the reason for evidence"), also circular evidence ( circulus in demonstrando or circulus in probando ), English begging the question , is an argumentative figure in which an assertion is substantiated by statements which presuppose the assertion to be proven to be true. This can be done explicitly, on the one hand, if the assertion is present as a conclusion or conclusion of an argument in which it occurs as a premise , and on the other hand, implicitly, in that the conclusion is not an explicit part of the argument, but is tacitly accepted.

A petitio principii can be a logically valid conclusion : From any given statement it follows unquestionably this itself. In this special case of an immediate circular reasoning, there is no fallacy from a formal point of view , the derivation is correct, but it is not a proof in the classical Aristotelian sense : If the premises of the proof are not different from the conclusion, the principle of sufficient reason is violated. In modern non-formal logic , however, Petitio principii is often recognized as an everyday figure of argument. The figure idem per idem is also a special case of the petitio or a logical figure that can be used for a petitio .

Types of the petitio principii

A petitio principii can be constructed in different ways. A premise does not support the conclusion if it is only

1. another formulation of the conclusion is:

   "Dodging is antisocial because it happens at the expense of paying passengers."

2. a generalization of the conclusion is:

   "Headache pills have undesirable side effects because all drugs have undesirable side effects."

3. is made out of thin air just to prove the conclusion:

   "I always take part in the carnival because I keep traditions."

Historical

The petitio was already described by Aristotle in the Organon as a fallacy . In the manual for the logic lecture by Immanuel Kant created by Gottlob Benjamin Jasche , it is dealt with in § 92 together with the circular reasoning ( circulum in probando ). (Immanuel Kant: AA IX, 135)

Examples

• "My brother doesn't like spinach, and that's lucky for my brother because if he did like it, he'd eat it and he can't stand it." - Here is the claim that it's lucky for the brother, Not liking spinach based on a petitio.
• I always tell the truth because
  • Truth is conformity of speech with reality.
  • Whoever says untruth is not talking about reality, that is, about nothing.
  • Anyone who talks about something is not talking about nothing, so is telling the truth.
• “Why do ideas in our minds agree with objects of experience even though they are not created by the experience itself? - To justify this with the principles of an epistemology would mean to prove intellectual ideas through intellectual ideas "

See also : ultimate reason

literature

• John Woods, Douglas Walton: Petitio principii . In: Synthesis , Vol. 31, No. 1, June 1975, pp. 107-127.
• L. Cummings: Petitio principii: the case for non-fallaciousness . In: Informal Logic , Volume 20, No. 1, pp. 1-18.

Web links

Wiktionary: Petitio Principii  - explanations of meanings, word origins, synonyms, translations

References and comments

1. ↑ Petitio Principii - Duden , Bibliographisches Institut, 2016
2. ^ Douglas J. Soccio, Vincent E. Barry: Practical Logic . 4th edition. Harcourt Brace Jovanovich College Publishers, 1992, ISBN 0-03-073907-1
3. ↑ Immanuel Kant, Collected Writings. Ed .: Vol. 1-22 Prussian Academy of Sciences, Vol. 23 German Academy of Sciences in Berlin, from Vol. 24 Academy of Sciences in Göttingen, Berlin 1900ff., AA IX, 135 .
4. ↑ Strictly speaking, the logically inadmissible use of a proposition as a self-evident axiom is discussed there under this designation: “A petitio principii is understood to mean the acceptance of a proposition as the ground of evidence as an immediately certain proposition, although it still requires proof. And one commits a circle in proving if one bases one's own evidence on the sentence that one wanted to prove. "
5. ↑ Nino Ferrer in the song "Madame Robert" from the music album Je veux être noir (1966) according to Pétition de principe in the French-language Wikipedia: "Mon frère n'aime pas les épinards, / et c'est heureux pour mon frère car, / s'il les aimait, il en mangerait / et il ne peut pas les supporter. » For the date of publication: Discography: les années 60. Je veux être noir. (No longer available online.) In: Official web site about Nino Ferrer. 2010, archived from the original on March 7, 2016 ; Retrieved on November 21, 2010 : "Année: 1966" Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.  
6. ↑ Wolfgang Röd : The Philosophy of Modern Times 3rd Part 1: Critical Philosophy from Kant to Schopenhauer . Munich 2006, p. 31