93 ideas
2797 | As coherence expands its interrelations become steadily tighter, culminating only in necessary truth [Dancy,J] |
2768 | The correspondence theory also has the problem that two sets of propositions might fit the facts equally well [Dancy,J] |
2765 | Rescher says that if coherence requires mutual entailment, this leads to massive logical redundancy [Dancy,J] |
2769 | If one theory is held to be true, all the other theories appear false, because they can't be added to the true one [Dancy,J] |
2766 | Even with a tight account of coherence, there is always the possibility of more than one set of coherent propositions [Dancy,J] |
15413 | With four tense operators, all complex tenses reduce to fourteen basic cases [Burgess] |
15415 | The temporal Barcan formulas fix what exists, which seems absurd [Burgess] |
15430 | Is classical logic a part of intuitionist logic, or vice versa? [Burgess] |
15431 | It is still unsettled whether standard intuitionist logic is complete [Burgess] |
15429 | Relevance logic's → is perhaps expressible by 'if A, then B, for that reason' [Burgess] |
15404 | Technical people see logic as any formal system that can be studied, not a study of argument validity [Burgess] |
15405 | Classical logic neglects the non-mathematical, such as temporality or modality [Burgess] |
15427 | The Cut Rule expresses the classical idea that entailment is transitive [Burgess] |
15421 | Classical logic neglects counterfactuals, temporality and modality, because maths doesn't use them [Burgess] |
15403 | Philosophical logic is a branch of logic, and is now centred in computer science [Burgess] |
15407 | Formalising arguments favours lots of connectives; proving things favours having very few [Burgess] |
15424 | Asserting a disjunction from one disjunct seems odd, but can be sensible, and needed in maths [Burgess] |
15409 | All occurrences of variables in atomic formulas are free [Burgess] |
15414 | The denotation of a definite description is flexible, rather than rigid [Burgess] |
15406 | 'Induction' and 'recursion' on complexity prove by connecting a formula to its atomic components [Burgess] |
15425 | The sequent calculus makes it possible to have proof without transitivity of entailment [Burgess] |
15426 | We can build one expanding sequence, instead of a chain of deductions [Burgess] |
15408 | 'Tautologies' are valid formulas of classical sentential logic - or substitution instances in other logics [Burgess] |
15418 | Validity (for truth) and demonstrability (for proof) have correlates in satisfiability and consistency [Burgess] |
15412 | Models leave out meaning, and just focus on truth values [Burgess] |
15411 | We only need to study mathematical models, since all other models are isomorphic to these [Burgess] |
15416 | We aim to get the technical notion of truth in all models matching intuitive truth in all instances [Burgess] |
15428 | The Liar seems like a truth-value 'gap', but dialethists see it as a 'glut' [Burgess] |
10185 | Set theory is the standard background for modern mathematics [Burgess] |
10184 | Structuralists take the name 'R' of the reals to be a variable ranging over structures, not a structure [Burgess] |
10189 | There is no one relation for the real number 2, as relations differ in different models [Burgess] |
10186 | If set theory is used to define 'structure', we can't define set theory structurally [Burgess] |
10187 | Abstract algebra concerns relations between models, not common features of all the models [Burgess] |
10188 | How can mathematical relations be either internal, or external, or intrinsic? [Burgess] |
2781 | Realism says that most perceived objects exist, and have some of their perceived properties [Dancy,J] |
15420 | De re modality seems to apply to objects a concept intended for sentences [Burgess] |
15419 | General consensus is S5 for logical modality of validity, and S4 for proof [Burgess] |
15417 | Logical necessity has two sides - validity and demonstrability - which coincide in classical logic [Burgess] |
15422 | Three conditionals theories: Materialism (material conditional), Idealism (true=assertable), Nihilism (no truth) [Burgess] |
15423 | It is doubtful whether the negation of a conditional has any clear meaning [Burgess] |
16285 | A possible world can be seen as a complete and consistent novel [Jeffrey] |
2745 | A pupil who lacks confidence may clearly know something but not be certain of it [Dancy,J] |
2755 | If senses are fallible, then being open to correction is an epistemological virtue [Dancy,J] |
5677 | Naïve direct realists hold that objects retain all of their properties when unperceived [Dancy,J] |
5678 | Scientific direct realism says we know some properties of objects directly [Dancy,J] |
5681 | Maybe we are forced from direct into indirect realism by the need to explain perceptual error [Dancy,J] |
5682 | Internal realism holds that we perceive physical objects via mental objects [Dancy,J] |
5683 | Indirect realism depends on introspection, the time-lag, illusions, and neuroscience [Dancy,J, by PG] |
2778 | Phenomenalism includes possible experiences, but idealism only refers to actual experiences [Dancy,J] |
5684 | Eliminative idealists say there are no objects; reductive idealists say objects exist as complex experiences [Dancy,J] |
2777 | Extreme solipsism only concerns current experience, but it might include past and future [Dancy,J] |
2794 | Knowing that a cow is not a horse seems to be a synthetic a priori truth [Dancy,J] |
2780 | Perception is either direct realism, indirect realism, or phenomenalism [Dancy,J] |
5679 | We can't grasp the separation of quality types, or what a primary-quality world would be like [Dancy,J] |
5680 | For direct realists the secondary and primary qualities seem equally direct [Dancy,J] |
2782 | We can be looking at distant stars which no longer actually exist [Dancy,J] |
2775 | It is not clear from the nature of sense data whether we should accept them as facts [Dancy,J] |
2784 | Appearances don't guarantee reality, unless the appearance is actually caused by the reality [Dancy,J] |
2785 | Perceptual beliefs may be directly caused, but generalisations can't be [Dancy,J] |
2788 | If perception and memory are indirect, then two things stand between mind and reality [Dancy,J] |
2787 | Memories aren't directly about the past, because time-lags and illusions suggest representation [Dancy,J] |
2791 | Phenomenalism about memory denies the past, or reduces it to present experience [Dancy,J] |
2790 | I can remember plans about the future, and images aren't essential (2+3=5) [Dancy,J] |
2754 | Foundations are justified by non-beliefs, or circularly, or they need no justification [Dancy,J] |
2749 | For internalists we must actually know that the fact caused the belief [Dancy,J] |
2770 | Internalists tend to favour coherent justification, but not the coherence theory of truth [Dancy,J] |
2752 | Foundationalism requires inferential and non-inferential justification [Dancy,J] |
2771 | Foundationalists must accept not only the basic beliefs, but also rules of inference for further progress [Dancy,J] |
2756 | If basic beliefs can be false, falsehood in non-basic beliefs might by a symptom [Dancy,J] |
2753 | Beliefs can only be infallible by having almost no content [Dancy,J] |
2773 | Coherentism gives a possible justification of induction, and opposes scepticism [Dancy,J] |
2779 | Idealists must be coherentists, but coherentists needn't be idealists [Dancy,J] |
2786 | For coherentists justification and truth are not radically different things [Dancy,J] |
2767 | If it is empirical propositions which have to be coherent, this eliminates coherent fiction [Dancy,J] |
2776 | Externalism could even make belief unnecessary (e.g. in animals) [Dancy,J] |
2746 | How can a causal theory of justification show that all men die? [Dancy,J] |
2747 | Causal theories don't allow for errors in justification [Dancy,J] |
2772 | Coherentism moves us towards a more social, shared view of knowledge [Dancy,J] |
2743 | What is the point of arguing against knowledge, if being right undermines your own argument? [Dancy,J] |
2751 | Probabilities can only be assessed relative to some evidence [Dancy,J] |
19155 | Instead of gambling, Jeffrey made the objects of Bayesian preference to be propositions [Jeffrey, by Davidson] |
2757 | The argument from analogy rests on one instance alone [Dancy,J] |
2758 | You can't separate mind and behaviour, as the analogy argument attempts [Dancy,J] |
2744 | Verificationism (the 'verification principle') is an earlier form of anti-realism [Dancy,J] |
2760 | Logical positivism implies foundationalism, by dividing weak from strong verifications [Dancy,J] |
2761 | If the meanings of sentences depend on other sentences, how did we learn language? [Dancy,J] |
2763 | There is an indeterminacy in juggling apparent meanings against probable beliefs [Dancy,J] |
2762 | Charity makes native beliefs largely true, and Humanity makes them similar to ours [Dancy,J] |
7260 | If there are intuited moral facts, why should we care about them? [Dancy,J] |
7261 | Internalists say that moral intuitions are motivating; externalist say a desire is also needed [Dancy,J] |
7262 | Obviously judging an action as wrong gives us a reason not to do it [Dancy,J] |
7265 | Moral facts are not perceived facts, but perceived reasons for judgements [Dancy,J] |
18681 | The base for values has grounds, catalysts and intensifiers [Dancy,J, by Orsi] |