Talk:Deductive fallacy

Latest comment: 8 years ago by Original Position in topic Merge with formal fallacy or delete the page

I can't think of why

  1. The average family has 2.5 children.
  2. The Smiths are an average family.
  3. Therefore, the Smiths must have 2 or 3 children.

is wrong. either provide an expelenation or remove it from the examples. —Preceding unsigned comment added by 132.77.4.43 (talk) 20:00, 20 January 2010 (UTC)Reply

Because the Smith's couldn't have 2.5 children, because that value is discrete SpitfireTally-ho! 13:13, 26 January 2010 (UTC)Reply
This is a confusing and bad example. The problem is your mixing a property of an entity clearly defined in the premise with ill-defined colloquial jargon in the second step. I am replacing it with something better. Byates5637 (talk) 01:29, 28 May 2010 (UTC)Reply

Logical fallacy

edit

Both the formal fallacy and the deductive fallacy articles claim that their alternative name is "Logical fallacy". Currently, Logical fallacy redirects to deductive fallacy. This needs to be clarified. --Piotr Konieczny aka Prokonsul Piotrus| talk 17:09, 1 April 2010 (UTC)Reply

Rename

edit

If this article is indeed the proper logical fallacy article, how about renaming it from Deductive fallacy to Logical fallacy per existing category? (We have Category:Logical fallacies but not Category:Deductive fallacies). --Piotr Konieczny aka Prokonsul Piotrus| talk 17:13, 1 April 2010 (UTC)Reply

Merge with formal fallacy or delete the page

edit

We have a page for formal fallacies, why do we need one for deductive fallacies as well. I believe these terms are generally used interchangeably the author cited for the definition seems to do so saying, "An invalid argument is also known as a formal fallacy or a deductive fallacy." The page tries to draw a distinction between the two by saying that some inductive arguments can be formally fallacious as well. Interesting and possibly true claim, but not citation is provided.

As it is, the page defines deductive fallacy to mean deductive invalidity. We already have a much better page on validity that discusses that concept, and under more standard terminology.

Finally, this page cites only a web page that refers to a self-published pamphlet by a philosophy professor to support its claims.

We should delete this page or merge it with formal fallacy as it covers essentially the same territory. If we can find sources to support the distinction, then perhaps a note in the page on validity or formal fallacies discussing it would be better than an entire page. Original Position (talk) 05:25, 14 February 2016 (UTC)Reply