Combining Texts

All the ideas for 'Intensional Logic', 'Truthmakers and Converse Barcan Formula' and 'Criterion of Validity in Reasoning'

expand these ideas     |    start again     |     specify just one area for these texts


23 ideas

2. Reason / A. Nature of Reason / 4. Aims of Reason
I reason in order to avoid disappointment and surprise [Peirce]
3. Truth / B. Truthmakers / 5. What Makes Truths / b. Objects make truths
The truthmaker principle requires some specific named thing to make the difference [Williamson]
3. Truth / B. Truthmakers / 7. Making Modal Truths
The converse Barcan formula will not allow contingent truths to have truthmakers [Williamson]
Truthmaker is incompatible with modal semantics of varying domains [Williamson]
3. Truth / H. Deflationary Truth / 1. Redundant Truth
That a judgement is true and that we judge it true are quite different things [Peirce]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
If metaphysical possibility is not a contingent matter, then S5 seems to suit it best [Williamson]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
If the domain of propositional quantification is constant, the Barcan formulas hold [Williamson]
Converse Barcan: could something fail to meet a condition, if everything meets that condition? [Williamson]
4. Formal Logic / E. Nonclassical Logics / 8. Intensional Logic
If terms change their designations in different states, they are functions from states to objects [Fitting]
Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting]
4. Formal Logic / E. Nonclassical Logics / 9. Awareness Logic
Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting]
4. Formal Logic / E. Nonclassical Logics / 10. Justification Logics
Justication logics make explicit the reasons for mathematical truth in proofs [Fitting]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Only study logic if you think your own reasoning is deficient [Peirce]
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
Classical logic is deliberately extensional, in order to model mathematics [Fitting]
5. Theory of Logic / F. Referring in Logic / 3. Property (λ-) Abstraction
λ-abstraction disambiguates the scope of modal operators [Fitting]
5. Theory of Logic / G. Quantification / 1. Quantification
Not all quantification is either objectual or substitutional [Williamson]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
Substitutional quantification is metaphysical neutral, and equivalent to a disjunction of instances [Williamson]
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
Not all quantification is objectual or substitutional [Williamson]
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
Facts are hard unmoved things, unaffected by what people may think of them [Peirce]
If 'fact' is a noun, can we name the fact that dogs bark 'Mary'? [Williamson]
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
Definite descriptions pick out different objects in different possible worlds [Fitting]
10. Modality / E. Possible worlds / 3. Transworld Objects / e. Possible Objects
Our ability to count objects across possibilities favours the Barcan formulas [Williamson]
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
A thing can't be the only necessary existent, because its singleton set would be as well [Williamson]