Combining Texts

All the ideas for 'Analyzing Modality', 'The Tragic Sense of Life' and 'Logic in Mathematics'

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


35 ideas

2. Reason / D. Definition / 3. Types of Definition
A 'constructive' (as opposed to 'analytic') definition creates a new sign [Frege]
2. Reason / D. Definition / 10. Stipulative Definition
Frege suggested that mathematics should only accept stipulative definitions [Frege, by Gupta]
2. Reason / E. Argument / 6. Conclusive Proof
We must be clear about every premise and every law used in a proof [Frege]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Logic not only proves things, but also reveals logical relations between them [Frege]
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
Does some mathematical reasoning (such as mathematical induction) not belong to logic? [Frege]
The closest subject to logic is mathematics, which does little apart from drawing inferences [Frege]
5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic
'Theorems' are both proved, and used in proofs [Frege]
5. Theory of Logic / G. Quantification / 3. Objectual Quantification
'All horses' either picks out the horses, or the things which are horses [Jubien]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Tracing inference backwards closes in on a small set of axioms and postulates [Frege]
The essence of mathematics is the kernel of primitive truths on which it rests [Frege]
Axioms are truths which cannot be doubted, and for which no proof is needed [Frege]
A truth can be an axiom in one system and not in another [Frege]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
To create order in mathematics we need a full system, guided by patterns of inference [Frege]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
If principles are provable, they are theorems; if not, they are axioms [Frege]
9. Objects / A. Existence of Objects / 1. Physical Objects
Being a physical object is our most fundamental category [Jubien]
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
Haecceities implausibly have no qualities [Jubien]
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
Every concept must have a sharp boundary; we cannot allow an indeterminate third case [Frege]
10. Modality / A. Necessity / 11. Denial of Necessity
De re necessity is just de dicto necessity about object-essences [Jubien]
10. Modality / C. Sources of Modality / 5. Modality from Actuality
Modal propositions transcend the concrete, but not the actual [Jubien]
Your properties, not some other world, decide your possibilities [Jubien]
Modal truths are facts about parts of this world, not about remote maximal entities [Jubien]
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
We have no idea how many 'possible worlds' there might be [Jubien]
If other worlds exist, then they are scattered parts of the actual world [Jubien]
If all possible worlds just happened to include stars, their existence would be necessary [Jubien]
If there are no other possible worlds, do we then exist necessarily? [Jubien]
Possible worlds just give parallel contingencies, with no explanation at all of necessity [Jubien]
Worlds don't explain necessity; we use necessity to decide on possible worlds [Jubien]
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
We mustn't confuse a similar person with the same person [Jubien]
18. Thought / B. Mechanics of Thought / 5. Mental Files
We need definitions to cram retrievable sense into a signed receptacle [Frege]
We use signs to mark receptacles for complex senses [Frege]
19. Language / A. Nature of Meaning / 6. Meaning as Use
A sign won't gain sense just from being used in sentences with familiar components [Frege]
19. Language / D. Propositions / 2. Abstract Propositions / a. Propositions as sense
Thoughts are not subjective or psychological, because some thoughts are the same for us all [Frege]
A thought is the sense expressed by a sentence, and is what we prove [Frege]
19. Language / D. Propositions / 5. Unity of Propositions
The parts of a thought map onto the parts of a sentence [Frege]
24. Political Theory / A. Basis of a State / 1. A People / a. Human distinctiveness
Maybe humans are distinguished from other animals by feelings, rather than reason [Unamuno]