170 ideas
9218 | Maybe what distinguishes philosophy from science is its pursuit of necessary truths [Sider] |
14721 | Metaphysical enquiry can survive if its conclusions are tentative [Sider] |
15010 | Your metaphysics is 'cheating' if your ontology won't support the beliefs you accept [Sider] |
14977 | Metaphysics is not about what exists or is true or essential; it is about the structure of reality [Sider] |
14994 | Extreme doubts about metaphysics also threaten to undermine the science of unobservables [Sider] |
15003 | It seems unlikely that the way we speak will give insights into the universe [Sider] |
14986 | Conceptual analysts trust particular intuitions much more than general ones [Sider] |
3348 | If phenomenology is deprived of the synthetic a priori, it is reduced to literature [Benardete,JA on Husserl] |
7614 | Bracketing subtracts entailments about external reality from beliefs [Husserl, by Putnam] |
6893 | Phenomenology aims to describe experience directly, rather than by its origins or causes [Husserl, by Mautner] |
22216 | Phenomenology studies different types of correlation between consciousness and its objects [Husserl, by Bernet] |
22218 | There can only be a science of fluctuating consciousness if it focuses on stable essences [Husserl, by Bernet] |
21217 | Phenomenology needs absolute reflection, without presuppositions [Husserl] |
22217 | Phenomenology aims to validate objects, on the basis of intentional intuitive experience [Husserl, by Bernet] |
22219 | Husserl saw transcendental phenomenology as idealist, in its construction of objects [Husserl, by Bernet] |
22204 | Start philosophising with no preconceptions, from the intuitively non-theoretical self-given [Husserl] |
22207 | Epoché or 'bracketing' is refraining from judgement, even when some truths are certain [Husserl] |
22208 | 'Bracketing' means no judgements at all about spatio-temporal existence [Husserl] |
22210 | After everything is bracketed, consciousness still has a unique being of its own [Husserl] |
22215 | Phenomenology describes consciousness, in the light of pure experiences [Husserl] |
15570 | Phenomenology is the science of essences - necessary universal structures for art, representation etc. [Husserl, by Polt] |
22201 | The use of mathematical-style definitions in philosophy is fruitless and harmful [Husserl] |
15015 | It seems possible for a correct definition to be factually incorrect, as in defining 'contact' [Sider] |
14981 | Philosophical concepts are rarely defined, and are not understood by means of definitions [Sider] |
14992 | We don't care about plain truth, but truth in joint-carving terms [Sider] |
15012 | Orthodox truthmaker theories make entities fundamental, but that is poor for explanation [Sider] |
13689 | 'Theorems' are formulas provable from no premises at all [Sider] |
13705 | Truth tables assume truth functionality, and are just pictures of truth functions [Sider] |
13706 | Intuitively, deontic accessibility seems not to be reflexive, but to be serial [Sider] |
13710 | In D we add that 'what is necessary is possible'; then tautologies are possible, and contradictions not necessary [Sider] |
13711 | System B introduces iterated modalities [Sider] |
13708 | S5 is the strongest system, since it has the most valid formulas, because it is easy to be S5-valid [Sider] |
13712 | Epistemic accessibility is reflexive, and allows positive and negative introspection (KK and K¬K) [Sider] |
13714 | We can treat modal worlds as different times [Sider] |
13720 | Converse Barcan Formula: □∀αφ→∀α□φ [Sider] |
13718 | The Barcan Formula ∀x□Fx→□∀xFx may be a defect in modal logic [Sider] |
13723 | System B is needed to prove the Barcan Formula [Sider] |
15023 | The Barcan schema implies if X might have fathered something, there is something X might have fathered [Sider] |
13715 | You can employ intuitionist logic without intuitionism about mathematics [Sider] |
15004 | 'Gunk' is an object in which proper parts all endlessly have further proper parts [Sider] |
14984 | Which should be primitive in mereology - part, or overlap? [Sider] |
14980 | There is a real issue over what is the 'correct' logic [Sider] |
15000 | 'It is raining' and 'it is not raining' can't be legislated, so we can't legislate 'p or ¬p' [Sider] |
15020 | Classical logic is good for mathematics and science, but less good for natural language [Sider] |
13678 | The most popular account of logical consequence is the semantic or model-theoretic one [Sider] |
13682 | Maybe logical consequence is impossibility of the premises being true and the consequent false [Sider] |
13680 | Maybe logical consequence is a primitive notion [Sider] |
13679 | Maybe logical consequence is more a matter of provability than of truth-preservation [Sider] |
15029 | Modal accounts of logical consequence are simple necessity, or essential use of logical words [Sider] |
13722 | A 'theorem' is an axiom, or the last line of a legitimate proof [Sider] |
21223 | Phenomenology grounds logic in subjective experience [Husserl, by Velarde-Mayol] |
21222 | Logicians presuppose a world, and ignore logic/world connections, so their logic is impure [Husserl, by Velarde-Mayol] |
15019 | Define logical constants by role in proofs, or as fixed in meaning, or as topic-neutral [Sider] |
13696 | When a variable is 'free' of the quantifier, the result seems incapable of truth or falsity [Sider] |
13700 | A 'total' function must always produce an output for a given domain [Sider] |
13703 | λ can treat 'is cold and hungry' as a single predicate [Sider] |
13688 | Good axioms should be indisputable logical truths [Sider] |
13687 | No assumptions in axiomatic proofs, so no conditional proof or reductio [Sider] |
13691 | Induction has a 'base case', then an 'inductive hypothesis', and then the 'inductive step' [Sider] |
13690 | Proof by induction 'on the length of the formula' deconstructs a formula into its accepted atoms [Sider] |
15001 | 'Tonk' is supposed to follow the elimination and introduction rules, but it can't be so interpreted [Sider] |
13685 | Natural deduction helpfully allows reasoning with assumptions [Sider] |
13686 | We can build proofs just from conclusions, rather than from plain formulae [Sider] |
13697 | Valuations in PC assign truth values to formulas relative to variable assignments [Sider] |
13684 | The semantical notion of a logical truth is validity, being true in all interpretations [Sider] |
13704 | It is hard to say which are the logical truths in modal logic, especially for iterated modal operators [Sider] |
13724 | In model theory, first define truth, then validity as truth in all models, and consequence as truth-preservation [Sider] |
13698 | In a complete logic you can avoid axiomatic proofs, by using models to show consequences [Sider] |
13699 | Compactness surprisingly says that no contradictions can emerge when the set goes infinite [Sider] |
9837 | 0 is not a number, as it answers 'how many?' negatively [Husserl, by Dummett] |
9576 | Multiplicity in general is just one and one and one, etc. [Husserl] |
17444 | Husserl said counting is more basic than Frege's one-one correspondence [Husserl, by Heck] |
21224 | Pure mathematics is the relations between all possible objects, and is thus formal ontology [Husserl, by Velarde-Mayol] |
13701 | A single second-order sentence validates all of arithmetic - but this can't be proved axiomatically [Sider] |
22209 | Our goal is to reveal a new hidden region of Being [Husserl] |
22211 | As a thing and its perception are separated, two modes of Being emerge [Husserl] |
14760 | Four-dimensionalism sees things and processes as belonging in the same category [Sider] |
15017 | Supervenience is a modal connection [Sider] |
15008 | Is fundamentality in whole propositions (and holistic), or in concepts (and atomic)? [Sider] |
15013 | Tables and chairs have fundamental existence, but not fundamental natures [Sider] |
21226 | Husserl sees the ego as a monad, unifying presence, sense and intentional acts [Husserl, by Velarde-Mayol] |
15014 | Unlike things, stuff obeys unrestricted composition and mereological essentialism [Sider] |
22202 | The World is all experiencable objects [Husserl] |
22213 | Absolute reality is an absurdity [Husserl] |
15009 | We must distinguish 'concrete' from 'abstract' and necessary states of affairs. [Sider] |
13692 | A 'precisification' of a trivalent interpretation reduces it to a bivalent interpretation [Sider] |
13693 | A 'supervaluation' assigns further Ts and Fs, if they have been assigned in every precisification [Sider] |
13695 | Supervaluational logic is classical, except when it adds the 'Definitely' operator [Sider] |
13694 | We can 'sharpen' vague terms, and then define truth as true-on-all-sharpenings [Sider] |
14983 | Accept the ontology of your best theory - and also that it carves nature at the joints [Sider] |
13683 | A relation is a feature of multiple objects taken together [Sider] |
14978 | A property is intrinsic if an object alone in the world can instantiate it [Sider] |
14194 | Proper ontology should only use categorical (actual) properties, not hypothetical ones [Sider] |
14995 | Predicates can be 'sparse' if there is a universal, or if there is a natural property or relation [Sider] |
14745 | If sortal terms fix the kind and the persistence conditions, we need to know what kinds there are [Sider] |
14740 | If Tib is all of Tibbles bar her tail, when Tibbles loses her tail, two different things become one [Sider] |
14752 | Artists 'create' statues because they are essentially statues, and so lack identity with the lump of clay [Sider] |
14743 | The stage view of objects is best for dealing with coincident entities [Sider] |
14747 | 'Composition as identity' says that an object just is the objects which compose it [Sider] |
21218 | The sense of anything contingent has a purely apprehensible essence or Eidos [Husserl] |
19263 | Imagine an object's properties varying; the ones that won't vary are the essential ones [Husserl, by Vaidya] |
14757 | Mereological essentialism says an object's parts are necessary for its existence [Sider] |
15026 | Essence (even if nonmodal) is not fundamental in metaphysics [Sider] |
14727 | Three-dimensionalists assert 'enduring', being wholly present at each moment, and deny 'temporal parts' [Sider] |
14738 | Some might say that its inconsistency with time travel is a reason to favour three-dimensionalism [Sider] |
14726 | Four-dimensionalists assert 'temporal parts', 'perduring', and being spread out over time [Sider] |
14728 | 4D says intrinsic change is difference between successive parts [Sider] |
14729 | 4D says each spatiotemporal object must have a temporal part at every moment at which it exists [Sider] |
14730 | Temporal parts exist, but are not prior building blocks for objects [Sider] |
14731 | Temporal parts are instantaneous [Sider] |
14758 | How can an instantaneous stage believe anything, if beliefs take time? [Sider] |
14762 | Four-dimensionalism says temporal parts are caused (through laws of motion) by previous temporal parts [Sider] |
14741 | The ship undergoes 'asymmetric' fission, where one candidate is seen as stronger [Sider] |
13702 | The identity of indiscernibles is necessarily true, if being a member of some set counts as a property [Sider] |
14754 | If you say Leibniz's Law doesn't apply to 'timebound' properties, you are no longer discussing identity [Sider] |
13721 | 'Strong' necessity in all possible worlds; 'weak' necessity in the worlds where the relevant objects exist [Sider] |
13707 | Maybe metaphysical accessibility is intransitive, if a world in which I am a frog is impossible [Sider] |
13709 | Logical truths must be necessary if anything is [Sider] |
13716 | 'If B hadn't shot L someone else would have' if false; 'If B didn't shoot L, someone else did' is true [Sider] |
15030 | Humeans say that we decide what is necessary [Sider] |
15031 | Modal terms in English are entirely contextual, with no modality outside the language [Sider] |
15027 | If truths are necessary 'by convention', that seems to make them contingent [Sider] |
15028 | Conventionalism doesn't seem to apply to examples of the necessary a posteriori [Sider] |
15033 | Humeans says mathematics and logic are necessary because that is how our concept of necessity works [Sider] |
15025 | The world does not contain necessity and possibility - merely how things are [Sider] |
13717 | Transworld identity is not a problem in de dicto sentences, which needn't identify an individual [Sider] |
14763 | Counterparts rest on similarity, so there are many such relations in different contexts [Sider] |
13719 | Barcan Formula problem: there might have been a ghost, despite nothing existing which could be a ghost [Sider] |
21220 | The physical given, unlike the mental given, could be non-existing [Husserl] |
21216 | Husserl says we have intellectual intuitions (of categories), as well as of the senses [Husserl, by Velarde-Mayol] |
22205 | Feelings of self-evidence (and necessity) are just the inventions of theory [Husserl] |
21221 | Direct 'seeing' by consciousness is the ultimate rational legitimation [Husserl] |
22220 | The phenomena of memory are given in the present, but as being past [Husserl, by Bernet] |
22206 | Natural science has become great by just ignoring ancient scepticism [Husserl] |
14988 | A theory which doesn't fit nature is unexplanatory, even if it is true [Sider] |
14982 | If I used Ramsey sentences to eliminate fundamentality from my theory, that would be a real loss [Sider] |
14997 | Two applications of 'grue' do not guarantee a similarity between two things [Sider] |
14989 | Problem predicates in induction don't reflect the structure of nature [Sider] |
14990 | Bayes produces weird results if the prior probabilities are bizarre [Sider] |
15005 | Explanations must cite generalisations [Sider] |
8406 | Not all explanations are causal, but if a thing can be explained at all, it can be explained causally [Sanford] |
15011 | If the ultimate explanation is a list of entities, no laws, patterns or mechanisms can be cited [Sider] |
22221 | We know another's mind via bodily expression, while also knowing it is inaccessible [Husserl, by Bernet] |
21228 | Husserl's monads (egos) communicate, through acts of empathy. [Husserl, by Velarde-Mayol] |
22212 | Pure consciousness is a sealed off system of actual Being [Husserl] |
15018 | Intentionality is too superficial to appear in the catalogue of ultimate physics [Sider] |
9575 | Husserl identifies a positive mental act of unification, and a negative mental act for differences [Husserl, by Frege] |
21225 | The psychological ego is worldly, and the pure ego follows transcendental reduction [Husserl, by Velarde-Mayol] |
22214 | We never meet the Ego, as part of experience, or as left over from experience [Husserl] |
21214 | We clarify concepts (e.g. numbers) by determining their psychological origin [Husserl, by Velarde-Mayol] |
9819 | Psychologism blunders in focusing on concept-formation instead of delineating the concepts [Dummett on Husserl] |
9851 | Husserl wanted to keep a shadowy remnant of abstracted objects, to correlate them [Dummett on Husserl] |
14999 | Prior to conventions, not all green things were green? [Sider] |
14998 | Conventions are contingent and analytic truths are necessary, so that isn't their explanation [Sider] |
15016 | Analyticity has lost its traditional role, which relied on truth by convention [Sider] |
22203 | Only facts follow from facts [Husserl] |
8407 | A totality of conditions necessary for an occurrence is usually held to be jointly sufficient for it [Sanford] |
14987 | Many of the key theories of modern physics do not appear to be 'laws' [Sider] |
14985 | The notion of law doesn't seem to enhance physical theories [Sider] |
14725 | Maybe motion is a dynamical quantity intrinsic to a thing at a particular time [Sider] |
14991 | Space has real betweenness and congruence structure (though it is not the Euclidean concepts) [Sider] |
14735 | Space is 3D and lacks a direction; time seems connected to causation [Sider] |
15021 | The central question in the philosophy of time is: How alike are time and space? [Sider] |
15024 | The spotlight theorists accepts eternal time, but with a spotlight of the present moving across it [Sider] |
14722 | Between presentism and eternalism is the 'growing block' view - the past is real, the future is not [Sider] |
14724 | Presentists must deny truths about multiple times [Sider] |
14756 | For Presentists there must always be a temporal vantage point for any description [Sider] |
14723 | Talk using tenses can be eliminated, by reducing it to indexical connections for an utterance [Sider] |
14734 | The B-series involves eternalism, and the reduction of tense [Sider] |
14736 | The B-theory is adequate, except that it omits to say which time is present [Sider] |