Timeline for What is the nature of "validity" in deduction when dealing with conclusions unrelated to premises?
Current License: CC BY-SA 4.0
14 events
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| Nov 14, 2020 at 20:11 | answer | added | Iamthereforeiam | timeline score: -4 | |
| Nov 14, 2020 at 16:44 | history | edited | J D | CC BY-SA 4.0 |
added 53 characters in body; edited tags; edited title
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| Nov 14, 2020 at 16:33 | answer | added | Floridus Floridi | timeline score: 1 | |
| Nov 14, 2020 at 3:04 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Oct 15, 2020 at 1:47 | answer | added | Bumble | timeline score: 0 | |
| Oct 14, 2020 at 22:51 | comment | added | Hypnosifl | Logical validity should depend only on the logical form, not on the semantic meaning of any of the terms. "This is an argument" may seem obviously true in context, but it isn't true for purely formal reasons. For example, we could replace "this" with the semantically meaningless symbol x and the predicate "is an argument" with a predicate symbol like p(), so "this is an argument" becomes just p(x). In such an abstract form, p(x) is neither tautological nor would it follow from either of the previous statements if they were also "translated" into such an abstract form. | |
| Oct 13, 2020 at 16:00 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jul 17, 2019 at 20:31 | answer | added | Speakpigeon | timeline score: 1 | |
| Mar 29, 2018 at 11:50 | history | tweeted | twitter.com/StackPhilosophy/status/979324841722556416 | ||
| Mar 21, 2018 at 2:47 | vote | accept | Zduff | ||
| Mar 19, 2018 at 20:10 | answer | added | Logikal | timeline score: 1 | |
| Mar 5, 2018 at 20:36 | comment | added | MarkOxford | If an argument has a logical truth (like p or not-p) as its conclusion, then the argument is indeed valid. It is impossible for the conclusion to be false, whence it is a fortiori also impossible for the premises to be true and the conclusion false. This is one of the limiting cases of validity - an argument with contradictory premises being another. The intuitive and technical concepts of validity part way here. Note that you’re using a demonstrative, this, in your example. Ordinary FOL can’t handle these expressions – essentially because they are context-sensitive. | |
| Mar 5, 2018 at 20:26 | review | First posts | |||
| Mar 6, 2018 at 2:12 | |||||
| Mar 5, 2018 at 20:25 | history | asked | Zduff | CC BY-SA 3.0 |