Combining Texts

All the ideas for 'Letter to Russell', 'The Common-Sense View of Reality' and 'Model Theory'

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

17 ideas

1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
7085 The main problem of philosophy is what can and cannot be thought and expressed [Wittgenstein, by Grayling]
1. Philosophy / E. Nature of Metaphysics / 2. Possibility of Metaphysics
20728 Metaphysics is hopeless with its present epistemology; common-sense realism is needed [Colvin]
2. Reason / D. Definition / 7. Contextual Definition
10476 The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
10478 Since first-order languages are complete, |= and |- have the same meaning [Hodges,W]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
10477 |= in model-theory means 'logical consequence' - it holds in all models [Hodges,W]
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
10474 |= should be read as 'is a model for' or 'satisfies' [Hodges,W]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
10475 A 'structure' is an interpretation specifying objects and classes of quantification [Hodges,W]
10473 Model theory studies formal or natural language-interpretation using set-theory [Hodges,W]
10481 Models in model theory are structures, not sets of descriptions [Hodges,W]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
10480 First-order logic can't discriminate between one infinite cardinal and another [Hodges,W]
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
23463 Atomic facts correspond to true elementary propositions [Wittgenstein]
7. Existence / D. Theories of Reality / 2. Realism
20726 We can only distinguish self from non-self if there is an inflexible external reality [Colvin]
20727 Common-sense realism rests on our interests and practical life [Colvin]
7. Existence / D. Theories of Reality / 4. Anti-realism
20730 If objects are doubted because their appearances change, that presupposes one object [Colvin]
20729 Arguments that objects are unknowable or non-existent assume the knower's existence [Colvin]
20731 The idea that everything is relations is contradictory; relations are part of the concept of things [Colvin]
19. Language / D. Propositions / 4. Mental Propositions
23490 A thought is mental constituents that relate to reality as words do [Wittgenstein]