121 ideas
3798 | An overexamined life is as bad as an unexamined one [Dennett] |
3801 | Rationality requires the assumption that things are either for better or worse [Dennett] |
10987 | Three traditional names of rules are 'Simplification', 'Addition' and 'Disjunctive Syllogism' [Read] |
11004 | Necessity is provability in S4, and true in all worlds in S5 [Read] |
11018 | There are fuzzy predicates (and sets), and fuzzy quantifiers and modifiers [Read] |
11011 | Same say there are positive, negative and neuter free logics [Read] |
11020 | Realisms like the full Comprehension Principle, that all good concepts determine sets [Read] |
14187 | If logic is topic-neutral that means it delves into all subjects, rather than having a pure subject matter [Read] |
10986 | Not all validity is captured in first-order logic [Read] |
10972 | The non-emptiness of the domain is characteristic of classical logic [Read] |
11024 | Semantics must precede proof in higher-order logics, since they are incomplete [Read] |
10985 | We should exclude second-order logic, precisely because it captures arithmetic [Read] |
14188 | Not all arguments are valid because of form; validity is just true premises and false conclusion being impossible [Read] |
14182 | If the logic of 'taller of' rests just on meaning, then logic may be the study of merely formal consequence [Read] |
14183 | Maybe arguments are only valid when suppressed premises are all stated - but why? [Read] |
10970 | A theory of logical consequence is a conceptual analysis, and a set of validity techniques [Read] |
10984 | Logical consequence isn't just a matter of form; it depends on connections like round-square [Read] |
14184 | In modus ponens the 'if-then' premise contributes nothing if the conclusion follows anyway [Read] |
14186 | Logical connectives contain no information, but just record combination relations between facts [Read] |
10973 | A theory is logically closed, which means infinite premisses [Read] |
11007 | Quantifiers are second-order predicates [Read] |
10978 | In second-order logic the higher-order variables range over all the properties of the objects [Read] |
10971 | A logical truth is the conclusion of a valid inference with no premisses [Read] |
10988 | Any first-order theory of sets is inadequate [Read] |
10974 | Compactness is when any consequence of infinite propositions is the consequence of a finite subset [Read] |
10975 | Compactness does not deny that an inference can have infinitely many premisses [Read] |
10977 | Compactness blocks the proof of 'for every n, A(n)' (as the proof would be infinite) [Read] |
10976 | Compactness makes consequence manageable, but restricts expressive power [Read] |
11014 | Self-reference paradoxes seem to arise only when falsity is involved [Read] |
11025 | Infinite cuts and successors seems to suggest an actual infinity there waiting for us [Read] |
10979 | Although second-order arithmetic is incomplete, it can fully model normal arithmetic [Read] |
10980 | Second-order arithmetic covers all properties, ensuring categoricity [Read] |
10997 | Von Neumann numbers are helpful, but don't correctly describe numbers [Read] |
11016 | Would a language without vagueness be usable at all? [Read] |
11019 | Supervaluations say there is a cut-off somewhere, but at no particular place [Read] |
11012 | A 'supervaluation' gives a proposition consistent truth-value for classical assignments [Read] |
11013 | Identities and the Indiscernibility of Identicals don't work with supervaluations [Read] |
14308 | We can bring dispositions into existence, as in creating an identifier [Dennett, by Mumford] |
10995 | A haecceity is a set of individual properties, essential to each thing [Read] |
7384 | Words are fixed by being attached to similarity clusters, without mention of 'essences' [Dennett] |
11001 | Equating necessity with truth in every possible world is the S5 conception of necessity [Read] |
10992 | The point of conditionals is to show that one will accept modus ponens [Read] |
10989 | The standard view of conditionals is that they are truth-functional [Read] |
11017 | Some people even claim that conditionals do not express propositions [Read] |
14185 | Conditionals are just a shorthand for some proof, leaving out the details [Read] |
2526 | Philosophers regularly confuse failures of imagination with insights into necessity [Dennett] |
3802 | Why pronounce impossible what you cannot imagine? [Dennett] |
10983 | Knowledge of possible worlds is not causal, but is an ontology entailed by semantics [Read] |
10982 | How can modal Platonists know the truth of a modal proposition? [Read] |
10996 | Actualism is reductionist (to parts of actuality), or moderate realist (accepting real abstractions) [Read] |
10981 | A possible world is a determination of the truth-values of all propositions of a domain [Read] |
11000 | If worlds are concrete, objects can't be present in more than one, and can only have counterparts [Read] |
7374 | Light wavelengths entering the eye are only indirectly related to object colours [Dennett] |
2523 | That every mammal has a mother is a secure reality, but without foundations [Dennett] |
3795 | Causal theories require the "right" sort of link (usually unspecified) [Dennett] |
7369 | Brains are essentially anticipation machines [Dennett] |
4608 | Minds are hard-wired, or trial-and-error, or experimental, or full self-aware [Dennett, by Heil] |
7393 | We can't draw a clear line between conscious and unconscious [Dennett] |
7367 | Perhaps the brain doesn't 'fill in' gaps in consciousness if no one is looking. [Dennett] |
4880 | Sentience comes in grades from robotic to super-human; we only draw a line for moral reasons [Dennett] |
2528 | Does consciousness need the concept of consciousness? [Dennett] |
2525 | Maybe language is crucial to consciousness [Dennett] |
7394 | Conscious events can only be explained in terms of unconscious events [Dennett] |
7391 | We can know a lot of what it is like to be a bat, and nothing important is unknown [Dennett] |
3158 | Theories of intentionality presuppose rationality, so can't explain it [Dennett] |
2527 | Unconscious intentionality is the foundation of the mind [Dennett] |
6624 | Dennett denies the existence of qualia [Dennett, by Lowe] |
4873 | What is it like to notice an uncomfortable position when you are asleep? [Dennett] |
7387 | "Qualia" can be replaced by complex dispositional brain states [Dennett] |
7658 | Obviously there can't be a functional anaylsis of qualia if they are defined by intrinsic properties [Dennett] |
7376 | We can't assume that dispositions will remain normal when qualia have been inverted [Dennett] |
7372 | In peripheral vision we see objects without their details, so blindsight is not that special [Dennett] |
7373 | Blindsight subjects glean very paltry information [Dennett] |
10998 | The mind abstracts ways things might be, which are nonetheless real [Read] |
3797 | I am the sum total of what I directly control [Dennett] |
7385 | People accept blurred boundaries in many things, but insist self is All or Nothing [Dennett] |
4881 | Being a person must involve having second-order beliefs and desires (about beliefs and desires) [Dennett] |
7383 | The psychological self is an abstraction, not a thing in the brain [Dennett] |
7386 | Selves are not soul-pearls, but artefacts of social processes [Dennett] |
7381 | We tell stories about ourselves, to protect, control and define who we are [Dennett] |
7382 | We spin narratives about ourselves, and the audience posits a centre of gravity for them [Dennett] |
7370 | The brain is controlled by shifting coalitions, guided by good purposeful habits [Dennett] |
7655 | The work done by the 'homunculus in the theatre' must be spread amongst non-conscious agencies [Dennett] |
3800 | You can be free even though force would have prevented you doing otherwise [Dennett, by PG] |
3803 | Can we conceive of a being with a will freer than our own? [Dennett] |
3791 | Awareness of thought is a step beyond awareness of the world [Dennett] |
3794 | Foreknowledge permits control [Dennett] |
7379 | If an epiphenomenon has no physical effects, it has to be undetectable [Dennett] |
7365 | Dualism wallows in mystery, and to accept it is to give up [Dennett] |
3159 | Beliefs and desires aren't real; they are prediction techniques [Dennett] |
3796 | The active self is a fiction created because we are ignorant of our motivations [Dennett] |
3161 | If mind is just an explanation, the explainer must have beliefs [Rey on Dennett] |
3986 | The 'intentional stance' is a way of interpreting an entity by assuming it is rational and self-aware [Dennett] |
2530 | Could a robot be made conscious just by software? [Dennett] |
7371 | All functionalism is 'homuncular', of one grain size or another [Dennett] |
4875 | We descend from robots, and our intentionality is composed of billions of crude intentional systems [Dennett] |
4879 | There is no more anger in adrenaline than silliness in a bottle of whiskey [Dennett] |
7657 | Intelligent agents are composed of nested homunculi, of decreasing intelligence, ending in machines [Dennett] |
7656 | I don't deny consciousness; it just isn't what people think it is [Dennett] |
7366 | It is arbitrary to say which moment of brain processing is conscious [Dennett] |
4876 | Maybe there is a minimum brain speed for supporting a mind [Dennett] |
7380 | Visual experience is composed of neural activity, which we find pleasing [Dennett] |
4878 | The materials for a mind only matter because of speed, and a need for transducers and effectors [Dennett] |
3177 | You couldn't drive a car without folk psychology [Dennett] |
3987 | Like the 'centre of gravity', desires and beliefs are abstract concepts with no actual existence [Dennett] |
4874 | The predecessor and rival of the language of thought hypothesis is the picture theory of ideas [Dennett] |
2524 | A language of thought doesn't explain content [Dennett] |
7654 | What matters about neuro-science is the discovery of the functional role of the chemistry [Dennett] |
23803 | States have content if we can predict them well by assuming intentionality [Dennett, by Schulte] |
3984 | The nature of content is entirely based on its functional role [Dennett] |
4882 | Concepts are things we (unlike dogs) can think about, because we have language [Dennett] |
2529 | Maybe there can be non-conscious concepts (e.g. in bees) [Dennett] |
11005 | Negative existentials with compositionality make the whole sentence meaningless [Read] |
10966 | A proposition objectifies what a sentence says, as indicative, with secure references [Read] |
3983 | Learning is evolution in the brain [Dennett] |
4872 | Most people see an abortion differently if the foetus lacks a brain [Dennett] |
6005 | Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley] |
7368 | Originally there were no reasons, purposes or functions; since there were no interests, there were only causes [Dennett] |
3985 | Biology is a type of engineering, not a search for laws of nature [Dennett] |
4877 | Maybe plants are very slow (and sentient) animals, overlooked because we are faster? [Dennett] |
3804 | Darwin's idea was the best idea ever [Dennett] |