Timeline for Does this make sense? Is it a contradiction? If a triangle has 2 sides, then it wouldn't be a triangle
Current License: CC BY-SA 3.0
19 events
| when toggle format | what | by | license | comment | |
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| Feb 21, 2018 at 1:12 | 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. | |
| Jan 22, 2018 at 0:38 | answer | added | JeffUK | timeline score: 0 | |
| Jan 21, 2018 at 22:39 | 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. | |
| Dec 22, 2017 at 22:02 | 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. | |
| Nov 22, 2017 at 21:35 | 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 26, 2017 at 22:36 | comment | added | Logikal | Did you just allude to something being ok to do because it is not illegal? If the rules do t say you cant do x that means you ahould do x? | |
| Oct 23, 2017 at 20:55 | answer | added | Logikal | timeline score: 0 | |
| Sep 28, 2017 at 4:34 | answer | added | Randy Buchholz | timeline score: 0 | |
| Sep 25, 2017 at 15:11 | comment | added | Jim H | You may find it interesting to also read about counterfactuals and counterfactual conditionals. | |
| Sep 25, 2017 at 12:04 | answer | added | JuliusCezarus | timeline score: 1 | |
| Sep 25, 2017 at 10:58 | review | Close votes | |||
| Oct 2, 2017 at 3:01 | |||||
| Sep 25, 2017 at 10:40 | comment | added | Swami Vishwananda | I'm voting to close this question as off-topic because this is word definitions, not philosophy | |
| Sep 25, 2017 at 9:12 | comment | added | Rob Hv | So it's like saying if (x is a triangle & x has 2 sides) and also (x is a triangle and not a triangle) there are 2 contradictions! thanks for your help! | |
| Sep 25, 2017 at 7:24 | comment | added | Mauro ALLEGRANZA | See Ex falso quodlibet: in "classical logic [and] intuitionistic logic any statement can be proven from a contradiction." Thus, according to the above "analysis", the inference: "if x is a triangle and x has two sides, then x is not a triangle" is correct. | |
| Sep 25, 2017 at 6:30 | comment | added | viuser | @MauroALLEGRANZA the question is if the whole sentence is a contradiction. | |
| Sep 25, 2017 at 6:14 | comment | added | Mauro ALLEGRANZA | From the def, we derive: (∀x) if x is a triangle, then x has three sides" as well as (∀x) if x has three sides, then x is a triangle". Thus, to assert: "x is a triangle and x has two sides (i.e. x does not have three sides)" is a contradiction. | |
| Sep 25, 2017 at 6:10 | comment | added | Mauro ALLEGRANZA | You cannot "analyze" it in purely propositional logic. In order to consider the correct "logical form" we need predicate logic, that is able to express the definition: "(a plane figure) x is a triangle iff x has three sides". | |
| Sep 25, 2017 at 3:44 | answer | added | viuser | timeline score: 0 | |
| Sep 25, 2017 at 2:21 | history | asked | Rob Hv | CC BY-SA 3.0 |