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All the ideas for 'Katzav on limitations of dispositions', 'Carnap and Logical Truth' and 'Logical Necessity'

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25 ideas

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
The logic of metaphysical necessity is S5 [Rumfitt]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
In order to select the logic justified by experience, we would need to use a lot of logic [Boghossian on Quine]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Elementary logic requires truth-functions, quantifiers (and variables), identity, and also sets of variables [Quine]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Logical consequence is marked by being preserved under all nonlogical substitutions [Quine, by Sider]
Soundness in argument varies with context, and may be achieved very informally indeed [Rumfitt]
There is a modal element in consequence, in assessing reasoning from suppositions [Rumfitt]
We reject deductions by bad consequence, so logical consequence can't be deduction [Rumfitt]
5. Theory of Logic / D. Assumptions for Logic / 3. Contradiction
Contradictions include 'This is red and not coloured', as well as the formal 'B and not-B' [Rumfitt]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
If logical truths essentially depend on logical constants, we had better define the latter [Hacking on Quine]
5. Theory of Logic / H. Proof Systems / 2. Axiomatic Proof
Geometrical axioms in logic are nowadays replaced by inference rules (which imply the logical truths) [Rumfitt]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / a. Set theory paradoxes
Set theory was struggling with higher infinities, when new paradoxes made it baffling [Quine]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
If set theory is not actually a branch of logic, then Frege's derivation of arithmetic would not be from logic [Quine]
8. Modes of Existence / E. Nominalism / 1. Nominalism / b. Nominalism about universals
Commitment to universals is as arbitrary or pragmatic as the adoption of a new system of bookkeeping [Quine]
10. Modality / A. Necessity / 3. Types of Necessity
A distinctive type of necessity is found in logical consequence [Rumfitt, by Hale/Hoffmann,A]
10. Modality / A. Necessity / 6. Logical Necessity
Frege moved Kant's question about a priori synthetic to 'how is logical certainty possible?' [Quine]
Logical necessity is when 'necessarily A' implies 'not-A is contradictory' [Rumfitt]
A logically necessary statement need not be a priori, as it could be unknowable [Rumfitt]
Narrow non-modal logical necessity may be metaphysical, but real logical necessity is not [Rumfitt]
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
If a world is a fully determinate way things could have been, can anyone consider such a thing? [Rumfitt]
12. Knowledge Sources / A. A Priori Knowledge / 7. A Priori from Convention
Examination of convention in the a priori begins to blur the distinction with empirical knowledge [Quine]
26. Natural Theory / B. Natural Kinds / 1. Natural Kinds
The natural kinds are objects, processes and properties/relations [Ellis]
26. Natural Theory / D. Laws of Nature / 2. Types of Laws
Least action is not a causal law, but a 'global law', describing a global essence [Ellis]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / a. Scientific essentialism
A species requires a genus, and its essence includes the essence of the genus [Ellis]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / c. Essence and laws
A hierarchy of natural kinds is elaborate ontology, but needed to explain natural laws [Ellis]
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / d. Knowing essences
Without general principles, we couldn't predict the behaviour of dispositional properties [Ellis]