56 ideas
| 23000 | Vicious regresses force you to another level; non-vicious imply another level [Baron/Miller] |
| 10888 | Sets can be defined by 'enumeration', or by 'abstraction' (based on a property) [Zalabardo] |
| 10889 | The 'Cartesian Product' of two sets relates them by pairing every element with every element [Zalabardo] |
| 10890 | A 'partial ordering' is reflexive, antisymmetric and transitive [Zalabardo] |
| 10886 | Determinacy: an object is either in a set, or it isn't [Zalabardo] |
| 10887 | Specification: Determinate totals of objects always make a set [Zalabardo] |
| 10897 | A first-order 'sentence' is a formula with no free variables [Zalabardo] |
| 10893 | Γ |= φ for sentences if φ is true when all of Γ is true [Zalabardo] |
| 10899 | Γ |= φ if φ is true when all of Γ is true, for all structures and interpretations [Zalabardo] |
| 10896 | Propositional logic just needs ¬, and one of ∧, ∨ and → [Zalabardo] |
| 10898 | The semantics shows how truth values depend on instantiations of properties and relations [Zalabardo] |
| 10902 | We can do semantics by looking at given propositions, or by building new ones [Zalabardo] |
| 10892 | We make a truth assignment to T and F, which may be true and false, but merely differ from one another [Zalabardo] |
| 10895 | 'Logically true' (|= φ) is true for every truth-assignment [Zalabardo] |
| 10900 | Logically true sentences are true in all structures [Zalabardo] |
| 10894 | A sentence-set is 'satisfiable' if at least one truth-assignment makes them all true [Zalabardo] |
| 10901 | Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo] |
| 10903 | A structure models a sentence if it is true in the model, and a set of sentences if they are all true in the model [Zalabardo] |
| 23024 | A traveller takes a copy of a picture into the past, gives it the artist, who then creates the original! [Baron/Miller] |
| 18085 | Values that approach zero, becoming less than any quantity, are 'infinitesimals' [Cauchy] |
| 18084 | When successive variable values approach a fixed value, that is its 'limit' [Cauchy] |
| 10891 | If a set is defined by induction, then proof by induction can be applied to it [Zalabardo] |
| 23008 | Grounding is intended as a relation that fits dependences between things [Baron/Miller] |
| 23018 | How does a changing object retain identity or have incompatible properties over time? [Baron/Miller] |
| 23011 | Modern accounts of causation involve either processes or counterfactuals [Baron/Miller] |
| 23013 | The main process theory of causation says it is transference of mass, energy, momentum or charge [Baron/Miller] |
| 23014 | If causes are processes, what is causation by omission? (Distinguish legal from scientific causes?) [Baron/Miller] |
| 23015 | The counterfactual theory of causation handles the problem no matter what causes actually are [Baron/Miller] |
| 23016 | Counterfactual theories struggle with pre-emption by a causal back-up system [Baron/Miller] |
| 23009 | There is no second 'law' of thermodynamics; it just reflects probabilities of certain microstates [Baron/Miller] |
| 23002 | In relativity space and time depend on one's motion, but spacetime gives an invariant metric [Baron/Miller] |
| 22988 | The block universe theory says entities of all times exist, and time is the B-series [Baron/Miller] |
| 22991 | How can we know this is the present moment, if other times are real? [Baron/Miller] |
| 22992 | If we are actually in the past then we shouldn't experience time passing [Baron/Miller] |
| 22994 | Erzatz Presentism allows the existence of other times, with only the present 'actualised' [Baron/Miller] |
| 22998 | How do presentists explain relations between things existing at different times? [Baron/Miller] |
| 23017 | Presentism needs endurantism, because other theories imply most of the object doesn't exist [Baron/Miller] |
| 23023 | How can presentists move to the next future moment, if that doesn't exist? [Baron/Miller] |
| 22995 | Most of the sciences depend on the concept of time [Baron/Miller] |
| 22993 | For abstractionists past times might still exist, althought their objects don't [Baron/Miller] |
| 23001 | The error theory of time's passage says it is either a misdescription or a false inference [Baron/Miller] |
| 22999 | It is meaningless to measure the rate of time using time itself, and without a rate there is no flow [Baron/Miller] |
| 22986 | The C-series rejects A and B, and just sees times as order by betweenness, without direction [Baron/Miller] |
| 22996 | The A-series has to treat being past, present or future as properties [Baron/Miller] |
| 23007 | The B-series can have a direction, as long as it does not arise from temporal flow [Baron/Miller] |
| 23003 | Static theories cannot account for time's obvious asymmetry, so time must be dynamic [Baron/Miller] |
| 23004 | The direction of time is either primitive, or reducible to something else [Baron/Miller] |
| 23005 | The kaon does not seem to be time-reversal invariant, unlike the rest of nature [Baron/Miller] |
| 23006 | Maybe the past is just the direction of decreasing entropy [Baron/Miller] |
| 23010 | We could explain time's direction by causation: past is the direction of causes, future of effects [Baron/Miller] |
| 22989 | Static time theory presents change as one property at t1, and a different property at t2 [Baron/Miller] |
| 23020 | If a time traveller kills his youthful grandfather, he both exists and fails to exist [Baron/Miller] |
| 23022 | Presentism means there no existing past for a time traveller to visit [Baron/Miller] |
| 22987 | The past (unlike the future) is fixed, along with truths about it, by the existence of past objects [Baron/Miller] |
| 22990 | The moving spotlight says entities can have properties of being present, past or future [Baron/Miller] |
| 22997 | The present moment is a matter of existence, not of acquiring a property [Baron/Miller] |