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From: Philip Johnson-Laird BA PhD Psychology (UCL), Stuart Professor of Psychology Emeritus at Princeton. (Author isn't a logician.) How We Reason (1st edn 2008). p. 145.

  1. Is there a term for the type of solution beneath, where one lists the Terms?

  2. Why don't Logic textbooks teach this method? They only use Venn Diagrams or Truth Tables.

In contrast, other syllogisms are so difficult that hardly anyone makes a correct response to them. If you want to test yourself, try this problem:

None of the artists is a beekeeper.
All the beekeepers are chemists.
What, if anything, follows?

The solution is on p. 147:

enter image description here

  • Three thoughts. (1) As written, the answers will be primarily opinion-based. (2) on that, my opinion is that there's no benefit to doing this over using contemporary quantified logic and it's harder to follow (at least glancing at it) than a venn diagram. (3) did you create a new username ? – virmaior Jul 9 '18 at 4:20
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    Also because the use of syllogisms themselves is not widespread. Math took over from Aristotle long ago, with simpler rules and more adequate descriptions and depictions for an equivalent logic. – jobermark Jul 18 '18 at 19:53
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    The conclusion only follows if there exists at least one beekeeper, which depends on how statements imply existence. Using standard first-order predicate calculus, "for all" does not imply "there exists". The system in Lewis Carroll's "Game of Logic" assumes that "All B are C" means "some B are C" and "no B are not-C", and thus there would have to be at least one beekeeper in existence. – David Thornley Aug 17 '18 at 21:25
  • Fundamentally... This method of reasoning will always lead to fallacy, unless the data is finite and fully qualified. Great in rules based big data analysis... Not so good in general argument. – Richard Aug 17 '18 at 23:01
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Is there a term for the type of solution beneath, where one lists the Terms?

The name of the syllogism is AEE in the first figure. Is that label the term you were looking for?

Here, the general form is: All Bs are Cs; No As are Bs; therefore No As are Cs. This general form transposes the two premises; it states first the major premise, because the major premise contains the predicate of the syllogism’s conclusion.

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    That doesn't follow. An A could be a C, since we aren't given anything to the contrary. All Bs are Cs, no As are Cs implies that no As are Bs. – David Thornley Aug 17 '18 at 21:18
  • "Is that label the term you were looking for?" No. I'm asking about this method of listing Terms, not what the Syllogism is called. – Edge Aug 24 '18 at 2:22
  • all men are mortal. no women are men. no women are mortal. doesn't follow, surely? you should include reference to that – another_name Apr 15 at 1:49
  • @another_name The syllogism is invalid. A term (C) distributed in the conclusion is not distributed in the premise. – Mark Andrews Apr 16 at 1:09
  • @DavidThornley Sorry for the delayed reply. See my reply to another _name. – Mark Andrews Apr 16 at 1:11

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