48 ideas
13838 | A decent modern definition should always imply a semantics [Hacking] |
23000 | Vicious regresses force you to another level; non-vicious imply another level [Baron/Miller] |
13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
23024 | A traveller takes a copy of a picture into the past, gives it the artist, who then creates the original! [Baron/Miller] |
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] |
21097 | Modern monarchies are (like republics) rule by law, rather than by men [Hume] |
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] |