Combining Texts

All the ideas for 'works', 'Modal Logic within Counterfactual Logic' and 'World and Essence'

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23 ideas

3. Truth / A. Truth Problems / 2. Defining Truth
In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski]
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Tarski, by Davidson]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
In S5 matters of possibility and necessity are non-contingent [Williamson]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
There is no clear boundary between the logical and the non-logical [Tarski]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
Logical consequence is when in any model in which the premises are true, the conclusion is true [Tarski, by Beall/Restall]
Logical consequence: true premises give true conclusions under all interpretations [Tarski, by Hodges,W]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Tarski improved Hilbert's geometry axioms, and without set-theory [Tarski, by Feferman/Feferman]
9. Objects / A. Existence of Objects / 4. Impossible objects
Plantinga proposes necessary existent essences as surrogates for the nonexistent things [Plantinga, by Stalnaker]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
The 'identity criteria' of a name are a group of essential and established facts [Plantinga]
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
'Being Socrates' and 'being identical with Socrates' characterise Socrates, so they are among his properties [Plantinga]
9. Objects / D. Essence of Objects / 2. Types of Essence
Does Socrates have essential properties, plus a unique essence (or 'haecceity') which entails them? [Plantinga]
9. Objects / D. Essence of Objects / 9. Essence and Properties
Properties are 'trivially essential' if they are instantiated by every object in every possible world [Plantinga]
X is essentially P if it is P in every world, or in every X-world, or in the actual world (and not ¬P elsewhere) [Plantinga]
If a property is ever essential, can it only ever be an essential property? [Plantinga]
Essences are instantiated, and are what entails a thing's properties and lack of properties [Plantinga]
9. Objects / F. Identity among Objects / 5. Self-Identity
Does 'being identical with Socrates' name a property? I can think of no objections to it [Plantinga]
10. Modality / A. Necessity / 1. Types of Modality
Necessity is counterfactually implied by its negation; possibility does not counterfactually imply its negation [Williamson]
10. Modality / A. Necessity / 4. De re / De dicto modality
'De re' modality is as clear as 'de dicto' modality, because they are logically equivalent [Plantinga]
10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
Strict conditionals imply counterfactual conditionals: □(A⊃B)⊃(A□→B) [Williamson]
10. Modality / B. Possibility / 9. Counterfactuals
Counterfactual conditionals transmit possibility: (A□→B)⊃(◊A⊃◊B) [Williamson]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Rather than define counterfactuals using necessity, maybe necessity is a special case of counterfactuals [Williamson, by Hale/Hoffmann,A]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
We can imagine being beetles or alligators, so it is possible we might have such bodies [Plantinga]
15. Nature of Minds / C. Capacities of Minds / 2. Imagination
Imagination is important, in evaluating possibility and necessity, via counterfactuals [Williamson]