display all the ideas for this combination of texts
4 ideas
13692 | A 'precisification' of a trivalent interpretation reduces it to a bivalent interpretation [Sider] |
Full Idea: For a 'precisification' we take a trivalent interpretation and preserve the T and F values, and then assign all the third values in some way to either T or F. | |
From: Theodore Sider (Logic for Philosophy [2010], 3.4.5) | |
A reaction: [my informal summary of Sider's formal definition] |
13693 | A 'supervaluation' assigns further Ts and Fs, if they have been assigned in every precisification [Sider] |
Full Idea: In a 'supervaluation' we take a trivalent interpretation, and assign to each wff T (or F) if it is T (or F) in every precisification, leaving the third truth-value in any other cases. The wffs are then 'supertrue' or 'superfalse' in the interpretation. | |
From: Theodore Sider (Logic for Philosophy [2010], 3.4.5) | |
A reaction: [my non-symbolic summary] Sider says the Ts and Fs in the precisifications are assigned 'in any way you like', so supervaluation is a purely formal idea, not a technique for eliminating vagueness. |
13695 | Supervaluational logic is classical, except when it adds the 'Definitely' operator [Sider] |
Full Idea: Supervaluation preserves classical logic (even though supervaluations are three-valued), except when we add the Δ operator (meaning 'definitely' or 'determinately'). | |
From: Theodore Sider (Logic for Philosophy [2010], 3.4.5) |
13694 | We can 'sharpen' vague terms, and then define truth as true-on-all-sharpenings [Sider] |
Full Idea: We can introduce 'sharpenings', to make vague terms precise without disturbing their semantics. Then truth (or falsity) becomes true(false)-in-all-sharpenings. You are only 'rich' if you are rich-on-all-sharpenings of the word. | |
From: Theodore Sider (Logic for Philosophy [2010], 3.4.5) | |
A reaction: Not very helpful. Lots of people might be considered rich in many contexts, but very few people would be considered rich in all contexts. You are still left with some vague middle ground. |