Talk:Lewis's triviality result
Appearance
This article is rated Start-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||||||||||||||||||||||||
|
A → B
[edit]Figure 1 purports to show [A → B] as one of the sets in the Venn diagram. But if [A → B] means the same thing as what it is usually taken to mean in propositional logic, then [A → B] is the same thing as [B ∪ A′ ]. Thus its probability should be 1 − x − y, or equivalently, s + t + u + v + w + z. How can the set labeled [A → B] in Figure 1 be regared as [A → B]? Michael Hardy (talk) 22:08, 27 September 2018 (UTC) @Knorlin:
- ok, So it appears that the expression “[A → B]” is not intended to mean what it usually means in propositional logic. I think the article should be explicit about that. Michael Hardy (talk) 22:25, 27 September 2018 (UTC)
- I added a clarifying note to the figure caption. Thanks for the observation. Knorlin (talk • contribs) 17:41, 8 March 2021 (UTC)
- "[A → B] is the same thing as [B ∪ A′ ]."
- This is wrong. See the truth table here https://en.wikipedia.org/wiki/Material_conditional
- When A is false, and B is true, A -> B is true. CrickedBack (talk) 07:45, 26 December 2022 (UTC)
Categories:
- Start-Class AfC articles
- AfC submissions by date/26 September 2018
- Accepted AfC submissions
- Start-Class mathematics articles
- Unknown-priority mathematics articles
- Start-Class Philosophy articles
- Low-importance Philosophy articles
- Start-Class logic articles
- Low-importance logic articles
- Logic task force articles
- Start-Class Analytic philosophy articles
- Low-importance Analytic philosophy articles
- Analytic philosophy task force articles