77 ideas
3593 | The only way to specify the corresponding fact is asserting the sentence [Williams,M] |
3584 | Justification needs coherence, while truth might be ideal coherence [Williams,M] |
3585 | Coherence needs positive links, not just absence of conflict [Williams,M] |
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] |
3599 | Deduction shows entailments, not what to believe [Williams,M] |
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] |
15421 | Classical logic neglects counterfactuals, temporality and modality, because maths doesn't use them [Burgess] |
15427 | The Cut Rule expresses the classical idea that entailment is transitive [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] |
15411 | We only need to study mathematical models, since all other models are isomorphic to these [Burgess] |
15412 | Models leave out meaning, and just focus on truth values [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] |
21110 | An understanding of the most basic physics should explain all of the subject's mysteries [Krauss] |
21105 | In 1676 it was discovered that water is teeming with life [Krauss] |
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] |
3591 | We could never pin down how many beliefs we have [Williams,M] |
3582 | Propositions make error possible, so basic experiential knowledge is impossible [Williams,M] |
3592 | Phenomenalism is a form of idealism [Williams,M] |
3579 | Sense data avoid the danger of misrepresenting the world [Williams,M] |
3581 | Sense data can't give us knowledge if they are non-propositional [Williams,M] |
3564 | Is it people who are justified, or propositions? [Williams,M] |
8851 | Coherentists say that regress problems are assuming 'linear' justification [Williams,M] |
3595 | What works always takes precedence over theories [Williams,M] |
8849 | Traditional foundationalism is radically internalist [Williams,M] |
8853 | Basic judgements are immune from error because they have no content [Williams,M] |
3580 | Experience must be meaningful to act as foundations [Williams,M] |
8855 | Sensory experience may be fixed, but it can still be misdescribed [Williams,M] |
3578 | Are empirical foundations judgements or experiences? [Williams,M] |
3576 | Foundationalists are torn between adequacy and security [Williams,M] |
3577 | Strong justification eliminates error, but also reduces our true beliefs [Williams,M] |
3590 | Coherence theory must give a foundational status to coherence itself [Williams,M] |
3589 | Why should diverse parts of our knowledge be connected? [Williams,M] |
3571 | Externalism does not require knowing that you know [Williams,M] |
3574 | Externalism ignores the social aspect of knowledge [Williams,M] |
3569 | In the causal theory of knowledge the facts must cause the belief [Williams,M] |
3586 | Only a belief can justify a belief [Williams,M] |
3567 | How could there be causal relations to mathematical facts? [Williams,M] |
3573 | Externalist reliability refers to a range of conventional conditions [Williams,M] |
3565 | Sometimes I ought to distrust sources which are actually reliable [Williams,M] |
3566 | We control our beliefs by virtue of how we enquire [Williams,M] |
8852 | In the context of scepticism, externalism does not seem to be an option [Williams,M] |
3594 | Scepticism just reveals our limited ability to explain things [Williams,M] |
3575 | Scepticism can involve discrepancy, relativity, infinity, assumption and circularity [Williams,M] |
3587 | Seeing electrons in a cloud chamber requires theory [Williams,M] |
3588 | Foundationalists base meaning in words, coherentists base it in sentences [Williams,M] |
21109 | Space itself can expand (and separate its contents) at faster than light speeds [Krauss] |
21104 | General Relativity: the density of energy and matter determines curvature and gravity [Krauss] |
21107 | Uncertainty says that energy can be very high over very short time periods [Krauss] |
21106 | Most of the mass of a proton is the energy in virtual particles (rather than the quarks) [Krauss] |
21112 | Empty space contains a continual flux of brief virtual particles [Krauss] |
21108 | The universe is precisely 13.72 billion years old [Krauss] |
21111 | It seems likely that cosmic inflation is eternal, and this would make a multiverse inevitable [Krauss] |