103 ideas
17774 | Definitions make our intuitions mathematically useful [Mayberry] |
17773 | Proof shows that it is true, but also why it must be true [Mayberry] |
15186 | In the tenseless view, all times are equally real, so statements of the future have truth-values [Le Poidevin] |
10455 | Free logic at least allows empty names, but struggles to express non-existence [Bach] |
17795 | Set theory can't be axiomatic, because it is needed to express the very notion of axiomatisation [Mayberry] |
17796 | There is a semi-categorical axiomatisation of set-theory [Mayberry] |
17800 | The misnamed Axiom of Infinity says the natural numbers are finite in size [Mayberry] |
17801 | The set hierarchy doesn't rely on the dubious notion of 'generating' them [Mayberry] |
17803 | Limitation of size is part of the very conception of a set [Mayberry] |
17786 | The mainstream of modern logic sees it as a branch of mathematics [Mayberry] |
17788 | First-order logic only has its main theorems because it is so weak [Mayberry] |
17791 | Only second-order logic can capture mathematical structure up to isomorphism [Mayberry] |
10454 | In first-order we can't just assert existence, and it is very hard to deny something's existence [Bach] |
10453 | In logic constants play the role of proper names [Bach] |
10452 | Proper names can be non-referential - even predicate as well as attributive uses [Bach] |
10456 | Millian names struggle with existence, empty names, identities and attitude ascription [Bach] |
10440 | An object can be described without being referred to [Bach] |
10444 | Definite descriptions can be used to refer, but are not semantically referential [Bach] |
17787 | Big logic has one fixed domain, but standard logic has a domain for each interpretation [Mayberry] |
17790 | No Löwenheim-Skolem logic can axiomatise real analysis [Mayberry] |
17779 | 'Classificatory' axioms aim at revealing similarity in morphology of structures [Mayberry] |
17778 | Axiomatiation relies on isomorphic structures being essentially the same [Mayberry] |
17780 | 'Eliminatory' axioms get rid of traditional ideal and abstract objects [Mayberry] |
17789 | No logic which can axiomatise arithmetic can be compact or complete [Mayberry] |
17784 | Real numbers can be eliminated, by axiom systems for complete ordered fields [Mayberry] |
17782 | Greek quantities were concrete, and ratio and proportion were their science [Mayberry] |
17781 | Real numbers were invented, as objects, to simplify and generalise 'quantity' [Mayberry] |
17799 | Cantor's infinite is an absolute, of all the sets or all the ordinal numbers [Mayberry] |
17797 | Cantor extended the finite (rather than 'taming the infinite') [Mayberry] |
17775 | If proof and definition are central, then mathematics needs and possesses foundations [Mayberry] |
17776 | The ultimate principles and concepts of mathematics are presumed, or grasped directly [Mayberry] |
17777 | Foundations need concepts, definition rules, premises, and proof rules [Mayberry] |
17804 | Axiom theories can't give foundations for mathematics - that's using axioms to explain axioms [Mayberry] |
17792 | 1st-order PA is only interesting because of results which use 2nd-order PA [Mayberry] |
17793 | It is only 2nd-order isomorphism which suggested first-order PA completeness [Mayberry] |
17794 | Set theory is not just first-order ZF, because that is inadequate for mathematics [Mayberry] |
17802 | We don't translate mathematics into set theory, because it comes embodied in that way [Mayberry] |
17805 | Set theory is not just another axiomatised part of mathematics [Mayberry] |
22919 | A thing which makes no difference seems unlikely to exist [Le Poidevin] |
17785 | Real numbers as abstracted objects are now treated as complete ordered fields [Mayberry] |
12900 | How could 'S knows he has hands' not have a fixed content? [Bach] |
12901 | If contextualism is right, knowledge sentences are baffling out of their context [Bach] |
12902 | Sceptics aren't changing the meaning of 'know', but claiming knowing is tougher than we think [Bach] |
15207 | We want illuminating theories, rather than coherent theories [Le Poidevin] |
22926 | In addition to causal explanations, they can also be inferential, or definitional, or purposive [Le Poidevin] |
10446 | Fictional reference is different inside and outside the fiction [Bach] |
10447 | We can refer to fictional entities if they are abstract objects [Bach] |
10443 | You 'allude to', not 'refer to', an individual if you keep their identity vague [Bach] |
10439 | What refers: indefinite or definite or demonstrative descriptions, names, indexicals, demonstratives? [Bach] |
10441 | If we can refer to things which change, we can't be obliged to single out their properties [Bach] |
10442 | We can think of an individual without have a uniquely characterizing description [Bach] |
10445 | It can't be real reference if it could refer to some other thing that satisfies the description [Bach] |
10457 | Since most expressions can be used non-referentially, none of them are inherently referential [Bach] |
10463 | Just alluding to or describing an object is not the same as referring to it [Bach] |
10459 | Context does not create reference; it is just something speakers can exploit [Bach] |
10460 | 'That duck' may not refer to the most obvious one in the group [Bach] |
10461 | What a pronoun like 'he' refers back to is usually a matter of speaker's intentions [Bach] |
10462 | Information comes from knowing who is speaking, not just from interpretation of the utterance [Bach] |
22932 | We don't just describe a time as 'now' from a private viewpoint, but as a fact about the world [Le Poidevin] |
10458 | People slide from contextual variability all the way to contextual determination [Bach] |
6866 | It is disturbing if we become unreal when we die, but if time is unreal, then we remain real after death [Le Poidevin] |
15190 | Evil can't be an illusion, because then the illusion that there is evil would be evil [Le Poidevin] |
6867 | Existentialism focuses on freedom and self-making, and insertion into the world [Le Poidevin] |
22927 | The logical properties of causation are asymmetry, transitivity and irreflexivity [Le Poidevin] |
22922 | We can identify unoccupied points in space, so they must exist [Le Poidevin] |
22924 | If spatial points exist, then they must be stationary, by definition [Le Poidevin] |
22923 | Absolute space explains actual and potential positions, and geometrical truths [Le Poidevin] |
22928 | For relationists moving an object beyond the edge of space creates new space [Le Poidevin] |
22931 | We distinguish time from space, because it passes, and it has a unique present moment [Le Poidevin] |
22917 | Since nothing occurs in a temporal vacuum, there is no way to measure its length [Le Poidevin] |
22921 | Temporal vacuums would be unexperienced, unmeasured, and unending [Le Poidevin] |
15195 | If the future is not real, we don't seem to have any obligation to future individuals [Le Poidevin] |
15188 | If things don't persist through time, then change makes no sense [Le Poidevin] |
22934 | Time can't speed up or slow down, so it doesn't seem to be a 'process' [Le Poidevin] |
15191 | At the very least, minds themselves seem to be tensed [Le Poidevin] |
15197 | Fiction seems to lack a tensed perspective, and offers an example of tenseless language [Le Poidevin] |
15206 | It is the view of the future that really decides between tensed and tenseless views of time [Le Poidevin] |
15198 | In the B-series, time-positions are unchanging; in the A-series they change (from future to present to past) [Le Poidevin] |
15189 | Things which have ceased change their A-series position; things that persist change their B-series position [Le Poidevin] |
6865 | A-theory says past, present, future and flow exist; B-theory says this just reports our perspective [Le Poidevin] |
15187 | It is claimed that the tense view entails the unreality of both future and past [Le Poidevin] |
15205 | Tensed theorists typically try to reduce the tenseless to the tensed [Le Poidevin] |
15192 | We share a common now, but not a common here [Le Poidevin] |
15193 | The new tenseless theory offers indexical truth-conditions, instead of a reductive analysis [Le Poidevin] |
22938 | To say that the past causes the present needs them both to be equally real [Le Poidevin] |
22939 | The B-series doesn't seem to allow change [Le Poidevin] |
22940 | If the B-universe is eternal, why am I trapped in a changing moment of it? [Le Poidevin] |
22953 | Time's arrow is not causal if there is no temporal gap between cause and effect [Le Poidevin] |
22947 | An ordered series can be undirected, but time favours moving from earlier to later [Le Poidevin] |
22952 | If time's arrow is causal, how can there be non-simultaneous events that are causally unconnected? [Le Poidevin] |
22951 | If time's arrow is psychological then different minds can impose different orders on events [Le Poidevin] |
22948 | There are Thermodynamic, Psychological and Causal arrows of time [Le Poidevin] |
22949 | Presumably if time's arrow is thermodynamic then time ends when entropy is complete [Le Poidevin] |
22950 | If time is thermodynamic then entropy is necessary - but the theory says it is probable [Le Poidevin] |
22943 | Instantaneous motion is an intrinsic disposition to be elsewhere [Le Poidevin] |
22945 | The dynamic view of motion says it is primitive, and not reducible to objects, properties and times [Le Poidevin] |
22937 | If the present could have diverse pasts, then past truths can't have present truthmakers [Le Poidevin] |
22925 | The present is the past/future boundary, so the first moment of time was not present [Le Poidevin] |
22944 | The primitive parts of time are intervals, not instants [Le Poidevin] |
22942 | If time is infinitely divisible, then the present must be infinitely short [Le Poidevin] |
22946 | The multiverse is distinct time-series, as well as spaces [Le Poidevin] |
15196 | God being inside or outside of time both raise a group of difficult problems [Le Poidevin] |
22941 | How could a timeless God know what time it is? So could God be both timeless and omniscient? [Le Poidevin] |