Combining Texts

All the ideas for 'Theory of Knowledge (2nd edn)', 'Logic in Mathematics' and 'Sameness and Substance'

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


51 ideas

1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / b. Seventeenth century philosophy
Most philosophers start with reality and then examine knowledge; Descartes put the study of knowledge first [Lehrer]
1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
You cannot demand an analysis of a concept without knowing the purpose of the analysis [Lehrer]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Semantic facts are preferable to transcendental philosophical fiction [Wiggins]
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 / 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]
A truth can be an axiom in one system and not in another [Frege]
Axioms are truths which cannot be doubted, and for which no proof is needed [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 / A. Nature of Mathematics / 4. Using Numbers / d. Counting via concepts
Maybe the concept needed under which things coincide must also yield a principle of counting [Wiggins]
The sortal needed for identities may not always be sufficient to support counting [Wiggins]
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]
7. Existence / D. Theories of Reality / 2. Realism
Realist Conceptualists accept that our interests affect our concepts [Wiggins]
Conceptualism says we must use our individuating concepts to grasp reality [Wiggins]
7. Existence / E. Categories / 3. Proposed Categories
Animal classifications: the Emperor's, fabulous, innumerable, like flies, stray dogs, embalmed…. [Wiggins]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
Individuation needs accounts of identity, of change, and of singling out [Wiggins]
Individuation can only be understood by the relation between things and thinkers [Wiggins]
9. Objects / A. Existence of Objects / 5. Individuation / c. Individuation by location
Singling out extends back and forward in time [Wiggins]
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
The only singling out is singling out 'as' something [Wiggins]
In Aristotle's sense, saying x falls under f is to say what x is [Wiggins]
Every determinate thing falls under a sortal, which fixes its persistence [Wiggins]
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]
9. Objects / D. Essence of Objects / 5. Essence as Kind
Natural kinds are well suited to be the sortals which fix substances [Wiggins]
9. Objects / D. Essence of Objects / 11. Essence of Artefacts
Artefacts are individuated by some matter having a certain function [Wiggins]
9. Objects / D. Essence of Objects / 13. Nominal Essence
Nominal essences don't fix membership, ignore evolution, and aren't contextual [Wiggins]
9. Objects / E. Objects over Time / 1. Objects over Time
'What is it?' gives the kind, nature, persistence conditions and identity over time of a thing [Wiggins]
9. Objects / E. Objects over Time / 7. Intermittent Objects
A restored church is the same 'church', but not the same 'building' or 'brickwork' [Wiggins]
A thing begins only once; for a clock, it is when its making is first completed [Wiggins]
9. Objects / E. Objects over Time / 9. Ship of Theseus
Priests prefer the working ship; antiquarians prefer the reconstruction [Wiggins]
9. Objects / F. Identity among Objects / 2. Defining Identity
Identity cannot be defined, because definitions are identities [Wiggins]
Leibniz's Law (not transitivity, symmetry, reflexivity) marks what is peculiar to identity [Wiggins]
Identity is primitive [Wiggins]
9. Objects / F. Identity among Objects / 6. Identity between Objects
A is necessarily A, so if B is A, then B is also necessarily A [Wiggins]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
By the principle of Indiscernibility, a symmetrical object could only be half of itself! [Wiggins]
9. Objects / F. Identity among Objects / 9. Sameness
We want to explain sameness as coincidence of substance, not as anything qualitative [Wiggins]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
It is hard or impossible to think of Caesar as not human [Wiggins]
13. Knowledge Criteria / E. Relativism / 5. Language Relativism
Our sortal concepts fix what we find in experience [Wiggins]
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]
18. Thought / D. Concepts / 2. Origin of Concepts / b. Empirical concepts
We conceptualise objects, but they impinge on us [Wiggins]
18. Thought / D. Concepts / 4. Structure of Concepts / f. Theory theory of concepts
A 'conception' of a horse is a full theory of what it is (and not just the 'concept') [Wiggins]
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]