52 ideas
| 23000 | Vicious regresses force you to another level; non-vicious imply another level [Baron/Miller] |
| Full Idea: A regress is vicious if the problem at level n can only be solved at level n+1; it is non-vicious if it can be solved at n, but the solution forces another level n+1, where the problem can be reformulated. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 2.3.2) | |
| A reaction: So in a vicious regress you chase the apparent solution, but never attain it. In the non-vicious you solve it, but then find you have a new problem. I think. |
| 23024 | A traveller takes a copy of a picture into the past, gives it the artist, who then creates the original! [Baron/Miller] |
| Full Idea: Suppose an art critic travels back in time with a copy of an artist's masterpiece, gives the artist the copy, and the artist copies it. The copy of the copy turns out to be the original mastepiece. The artwork seems to come from nowhere. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 8.6) | |
| A reaction: Lovely thought. Is the example possible (even with time travel)? How would the critic possess the copy before making the time journey? What if the critic decided not to travel back in time? Can a picture exist if no one has imagined it first? |
| 23008 | Grounding is intended as a relation that fits dependences between things [Baron/Miller] |
| Full Idea: Grounding is a posit introduced by metaphysicians in an attempt to devise a relation that can accommodate dependence between things in the world. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.6) | |
| A reaction: Grounding is a recent concept which seems to have lots of enemies, but I assume you can only reject it if you reject the concept of dependence - yet that seems a fairly obvious fact to me. My favoured metaphysical relation is 'determination'. |
| 23018 | How does a changing object retain identity or have incompatible properties over time? [Baron/Miller] |
| Full Idea: The problems of temporary intrinsics are reconciling the indiscernibility of identicals with change in an object over time, and the problem of something have incompatible properties over time (such as tired and not-tired). | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 7.3.1) | |
| A reaction: Loosely speaking, I would offer some sort of essentialism as the answer to these problems. People are not essentially sitting down, or tired. Or we can relativise properties to times t1 and t2. |
| 20014 | Actions include: the involuntary, the purposeful, the intentional, and the self-consciously autonomous [Wilson/Schpall] |
| Full Idea: There are different levels of action, including at least: unconscious and/or involuntary behaviour, purposeful or goal-directed activity, intentional action, and the autonomous acts or actions of self-consciously active human agents. | |
| From: Wilson,G/Schpall,S (Action [2012], 1) | |
| A reaction: The fourth class is obviously designed to distinguish us from the other animals. It immediately strikes me as very optimistic to distinguish four (at least) clear categories, but you have to start somewhere. |
| 20019 | Maybe bodily movements are not actions, but only part of an agent's action of moving [Wilson/Schpall] |
| Full Idea: Some say that the movement's of agent's body are never actions. It is only the agent's direct moving of, say, his leg that constitutes a physical action; the leg movement is merely caused by and/or incorporated as part of the act of moving. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.2) | |
| A reaction: [they cite Jennifer Hornsby 1980] It seems normal to deny a twitch the accolade of an 'action', so I suppose that is right. Does the continual movement of my tongue count as action? Only if I bring it under control? Does it matter? Only in forensics. |
| 20021 | Is the action the arm movement, the whole causal process, or just the trying to do it? [Wilson/Schpall] |
| Full Idea: Some philosophers have favored the overt arm movement the agent performs, some favor the extended causal process he initiates, and some prefer the relevant event of trying that precedes and 'generates' the rest. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.2) | |
| A reaction: [Davidson argues for the second, Hornsby for the third] There seems no way to settle this, and a compromise looks best. Mere movement won't do, and mere trying won't do, and whole processes get out of control. |
| 20022 | To be intentional, an action must succeed in the manner in which it was planned [Wilson/Schpall] |
| Full Idea: If someone fires a bullet to kill someone, misses, and dislodges hornets that sting him to death, this implies that an intentional action must include succeeding in a manner according to the original plan. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [their example, compressed] This resembles Gettier's problem cases for knowledge. If the shooter deliberately and maliciously brought down the hornet's nest, that would be intentional murder. Sounds right. |
| 20023 | If someone believes they can control the lottery, and then wins, the relevant skill is missing [Wilson/Schpall] |
| Full Idea: If someone enters the lottery with the bizarre belief that they can control who wins, and then wins it, that suggest that intentional actions must not depend on sheer luck, but needs competent exercise of the relevant skill. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: A nice companion to Idea 20022, which show that a mere intention is not sufficient to motivate and explain an action. |
| 20025 | We might intend two ways to acting, knowing only one of them can succeed [Wilson/Schpall] |
| Full Idea: If an agent tries to do something by two different means, only one of which can succeed, then the behaviour is rational, even though one of them is an attempt to do an action which cannot succeed. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [a concise account of a laborious account of an example from Bratman 1984, 1987] Bratman uses this to challenge the 'Simple View', that intention leads straightforwardly to action. |
| 20031 | On one model, an intention is belief-desire states, and intentional actions relate to beliefs and desires [Wilson/Schpall] |
| Full Idea: On the simple desire-belief model, an intention is a combination of desire-belief states, and an action is intentional in virtue of standing in the appropriate relation to these simpler terms. | |
| From: Wilson,G/Schpall,S (Action [2012], 4) | |
| A reaction: This is the traditional view found in Hume, and is probably endemic to folk psychology. They cite Bratman 1987 as the main opponent of the view. |
| 20028 | Groups may act for reasons held by none of the members, so maybe groups are agents [Wilson/Schpall] |
| Full Idea: Rational group action may involve a 'collectivising of reasons', with participants acting in ways that are not rationally recommended from the individual viewpoint. This suggests that groups can be rational, intentional agents. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [Pettit 2003] is the source for this. Gilbert says individuals can have joint commitment; Pettit says the group can be an independent agent. The matter of shared intentions is interesting, but there is no need for the ontology to go berserk. |
| 20027 | If there are shared obligations and intentions, we may need a primitive notion of 'joint commitment' [Wilson/Schpall] |
| Full Idea: An account of mutual obligation to do something may require that we give up reductive individualist accounts of shared activity and posit a primitive notion of 'joint commitment'. | |
| From: Wilson,G/Schpall,S (Action [2012], 2) | |
| A reaction: [attributed to Margaret Gilbert 2000] If 'we' are trying to do something, that seems to give an externalist picture of intentions, rather like all the other externalisms floating around these days. I don't buy any of it, me. |
| 20016 | Strong Cognitivism identifies an intention to act with a belief [Wilson/Schpall] |
| Full Idea: A Strong Cognitivist is someone who identifies an intention with a certain pertinent belief about what she is doing or about to do. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: (Sarah Paul 2009 makes this distinction) The belief, if so, seems to be as much counterfactual as factual. Hope seems to come into it, which isn't exactly a belief. |
| 20017 | Weak Cognitivism says intentions are only partly constituted by a belief [Wilson/Schpall] |
| Full Idea: A Weak Cognitivist holds that intentions are partly constituted by, but are not identical with, relevant beliefs about the action. Grice (1971) said an intention is willing an action, combined with a belief that this will lead to the action. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: [compressed] I didn't find Strong Cognitivism appealing, but it seems hard to argue with some form of the weak version. |
| 20018 | Strong Cognitivism implies a mode of 'practical' knowledge, not based on observation [Wilson/Schpall] |
| Full Idea: Strong Cognitivists say intentions/beliefs are not based on observation or evidence, and are causally reliable in leading to appropriate actions, so this is a mode of 'practical' knowledge that has not been derived from observation. | |
| From: Wilson,G/Schpall,S (Action [2012], 1.1) | |
| A reaction: [compressed - Stanford unnecessarily verbose!] I see no mention in this discussion of 'hoping' that your action will turn out OK. We are usually right to hope, but it would be foolish to say that when we reach for the salt we know we won't knock it over. |
| 20012 | Maybe the explanation of an action is in the reasons that make it intelligible to the agent [Wilson/Schpall] |
| Full Idea: Some have maintained that we explain why an agent acted as he did when we explicate how the agent's normative reasons rendered the action intelligible in his eyes. | |
| From: Wilson,G/Schpall,S (Action [2012], Intro) | |
| A reaction: Modern psychology is moving against this, by showing how hidden biases can predominate over conscious reasons (as in Kahnemann's work). I would say this mode of explanation works better for highly educated people (but you can chuckle at that). |
| 20029 | Causalists allow purposive explanations, but then reduce the purpose to the action's cause [Wilson/Schpall] |
| Full Idea: Most causalists allow that reason explanations are teleological, but say that such purposive explanations are analysable causally, where the primary reasons for the act are the guiding causes of the act. | |
| From: Wilson,G/Schpall,S (Action [2012], 3) | |
| A reaction: The authors observe that it is hard to adjudicate on this matter, and that the concept of the 'cause' of an action is unclear. |
| 20013 | It is generally assumed that reason explanations are causal [Wilson/Schpall] |
| Full Idea: The view that reason explanations are somehow causal explanations remains the dominant position. | |
| From: Wilson,G/Schpall,S (Action [2012], Intro) | |
| A reaction: I suspect that this is only because no philosopher has a better idea, and the whole issue is being slowly outflanked by psychology. |
| 16764 | The soul conserves the body, as we see by its dissolution when the soul leaves [Toletus] |
| Full Idea: Every accident of a living thing, as well as all its organs and temperaments and its dispositions are conserved by the soul. We see this from experience, since when that soul recedes, all these dissolve and become corrupted. | |
| From: Franciscus Toletus (Commentary on 'De Anima' [1572], II.1.1), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 24.5 | |
| A reaction: A nice example of observing a phenemonon, but not being able to observe the dependence relation the right way round. Compare Descartes in Idea 16763. |
| 23011 | Modern accounts of causation involve either processes or counterfactuals [Baron/Miller] |
| Full Idea: The two major contemporary theories of causation are process theories and counterfactual theories. …Process theories treat it as something to be discovered. …Counterfactual theories ignore processes, and treat it in terms of truth and falsity. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 6.1) | |
| A reaction: I take the counterfactual theory to be a specialised branch of the project of analytic metaphysics, which seeks the logical form of causation sentences, using possible worlds semantics. In the real word its processes or nothing. |
| 23013 | The main process theory of causation says it is transference of mass, energy, momentum or charge [Baron/Miller] |
| Full Idea: According to contemporary process theories of causation it consists of the transference of a 'mark', which is always some conserved quantity. Candidates (from science) are mass, energy, momentum and electric charge. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 6.2.2) | |
| A reaction: Given my commitment to physicalism, this is my preferred theory of causation. It began with the suggestion of energy-transfer, but has broadened into the present idea. It is an updated version of the Newton view, as the meeting of objects. |
| 23014 | If causes are processes, what is causation by omission? (Distinguish legal from scientific causes?) [Baron/Miller] |
| Full Idea: Process theories of causation face a serious problem, such as killing a plant by failing to water it - a cause by omission. …Defenders of the theory propose two concepts of causation: one for legal and one for scientific contexts. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 6.2.3) | |
| A reaction: Not much of a problem, I think. Clearly the scientific concept has priority. The plant died of dehydration, resulting from the consumption and evaporation of the available water. The human causes of that situation are legion. |
| 23015 | The counterfactual theory of causation handles the problem no matter what causes actually are [Baron/Miller] |
| Full Idea: The chief advantage of the counterfactual theory of causation is that it is flexible enough to handle causation no matter what in the world underlies the causal facts in question. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 6.3) | |
| A reaction: It has this advantage because it makes no attempt to explain causation, but merely gives an accurate map of the truth and falsity of causal statements. It describes how we think about causation. |
| 23016 | Counterfactual theories struggle with pre-emption by a causal back-up system [Baron/Miller] |
| Full Idea: Counterfactual theories of causation have difficulty accommodating pre-emption, which involves the existence of causal back-up systems that undermine counterfactual dependence. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 6.5) | |
| A reaction: E.g. If your stone hadn't broken the window first, my stone would have broken it instead. So in the nearest world the withholding of your stone doesn't save the window. |
| 23009 | There is no second 'law' of thermodynamics; it just reflects probabilities of certain microstates [Baron/Miller] |
| Full Idea: According to contemporary statistical mechanics the second law of thermodynamics is not really a law at all, but merely reflects to probabilities of certain microstates, conditional on local boundary conditions having certain properties. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.6.1) | |
| A reaction: A nice illustration of how metaphysicians have been seduced by the 'laws' of nature into falsely inferring all sorts of natural necessities. Entropy is normally assumed to be totally inevitable, because of some natural force. It's just a pattern. |
| 23002 | In relativity space and time depend on one's motion, but spacetime gives an invariant metric [Baron/Miller] |
| Full Idea: While spatial and temporal distances in relativity depend on one's relative state of motion, spatiotemporal distances within Minkowski spacetime do not. It therefore provides an invariant metric for describing the distances between things. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 4.2) | |
| A reaction: I doubt whether this solves all the worries which philosophers have, about relativity giving an account of time which contradicts our concept of time in every other area of our understanding. |
| 22988 | The block universe theory says entities of all times exist, and time is the B-series [Baron/Miller] |
| Full Idea: The standard block universe theory combines EntityEverywhenism with the B-theory of time. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.4) | |
| A reaction: This is also known as 'eternalism'. These authors emphasise that there is an ontological commitment to the objects of past and future in eternalism, as well as the B-series view of the moments of time. |
| 22991 | How can we know this is the present moment, if other times are real? [Baron/Miller] |
| Full Idea: According to the spotlight and growing block views, there is a single objectively present moment, and also other objectively existing moments. But then how do persons in those different moments know which one is present? | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.6) | |
| A reaction: [compressed example] This sceptical thought leads either towards Presentism (we know we are present because that's all there is), or Eternalism (there is no present moment, so no problem). A good objection to spotlight and growing block. |
| 22992 | If we are actually in the past then we shouldn't experience time passing [Baron/Miller] |
| Full Idea: If the past really exists, and we are in it, rather than in the present, then we should rationally conclude that we are not experiencing the passage of time. …But then we have no basis for arguing that time is dynamic. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.6) | |
| A reaction: [compressed] It is certainly difficult to conceive how past times and entities could be real in every way, except that the experience of time passing has been removed. But if past people experience passing, they must believe they are present… |
| 22994 | Erzatz Presentism allows the existence of other times, with only the present 'actualised' [Baron/Miller] |
| Full Idea: The 'erzatz presentism' view is that either the past and present exist, or all times exist, but only the present is 'actualised'. Standard Presentism says no times exist other than the present. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.7.2) | |
| A reaction: Ersatz presentism is obviously a close relative of the moving spotlight and growing block views. No account seems possible of the distinction between 'exists' and 'actualised' (other than the former being a mere abstract concept). |
| 22998 | How do presentists explain relations between things existing at different times? [Baron/Miller] |
| Full Idea: A chief challenge facing presentism is how to give an account of cross-temporal relations, which link things that exist with things that do not. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 2.2) | |
| A reaction: The problem of whether to keep a dubious death-bed promise is a bit of a puzzle for all of us, whatever our metaphysical view of time. None of us deny the reality of our great-great-grandparents. |
| 23017 | Presentism needs endurantism, because other theories imply most of the object doesn't exist [Baron/Miller] |
| Full Idea: Presentism is more naturally paired with endurantism, since if we pair it with perdurantism or transdurantism we have to say that most of any persisting object does not exist, and while that is not incoherent it is not very attractive. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 7.2.2) | |
| A reaction: (I think perdurance is time slices, and transdurance is the complete time worm). My preferred combination is this one: all that exists is the complete objects at the present moment. It also needs strong commitment to the truth of tensed verbs. |
| 23023 | How can presentists move to the next future moment, if that doesn't exist? [Baron/Miller] |
| Full Idea: If Presentism is true, how do we manage to travel from this moment to the next moment, a moment that is, at present, a future and hence non-existent moment? | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 8.3.1) | |
| A reaction: The reply would have to be that the metaphor of 'travel' is inappropriate for the movement through time. Travel needs a succession of existing places. The advancement of time is nothing like that. Nice question, though. |
| 22995 | Most of the sciences depend on the concept of time [Baron/Miller] |
| Full Idea: Without time it is hard to make sense of historical research, evolutionary biology, psychology, chemistry, biology, cosmology, social science, archaeology, practical reason, evidence, human agency and causation. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.8) | |
| A reaction: [compressed] I do find it extraordinary that relativistic physicists cheerfully embrace an eternalist theory of time which seems to render nearly all of the other sciences meaningless. |
| 22993 | For abstractionists past times might still exist, althought their objects don't [Baron/Miller] |
| Full Idea: If past moments are seen as abstract (rather than concrete) it doesn't follow that because past objects no longer exist that therefore past times do not exist. The abstractionist needs to say which times are concretely realised. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.7.2) | |
| A reaction: Abstractionists see times as representations of change, rather than as substances. |
| 23001 | The error theory of time's passage says it is either a misdescription or a false inference [Baron/Miller] |
| Full Idea: According to the cognitive error theory of the passage of time, …it is either our misdescription of our temporal phenomenology, or some mechanism of our brain infers that the phenomenology is caused by time actually passing. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 3.3.1) | |
| A reaction: [compressed] I think I have some sympathy with the misdescription view. If you imaginatively gradually remove all the changing events in your experience, that doesn't end with a raw experience of pure time, because there is no such thing. |
| 22999 | It is meaningless to measure the rate of time using time itself, and without a rate there is no flow [Baron/Miller] |
| Full Idea: It seems we are forced to measure the rate of time's passing against itself. But that's just not a meaningful rate. So time has no rate. So it doesn't flow. So there is no such thing as temporal passage. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 2.3.1) | |
| A reaction: It is suggested that you can exchange dollars one for one, so time might move at one second per second. But you can't exchange your own dollars with yourself at one-for-one. That is meaningless. Time is NOT a substance which flows. |
| 22986 | The C-series rejects A and B, and just sees times as order by betweenness, without direction [Baron/Miller] |
| Full Idea: The C-series sees times not as directed, but as unchanging, and ordered in terms of the betweenness relation. The C-theory also asserts that the A-series and B-series do not exist. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.2) | |
| A reaction: This is McTaggart's idea. Compare this with A-series ordering by past, present and future, and B-series ordering by earlier-than, later-than and simultaneous. The main point is that A and B have a direction, but C does not. |
| 22996 | The A-series has to treat being past, present or future as properties [Baron/Miller] |
| Full Idea: One of the limitations of the A-series is that temporal passage then presupposes the existence of properties of being present, being past and being future. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 2.1) | |
| A reaction: Metaphysicians happily talk about 'properties' all the time, and most of them never grasp how ambiguous and obscure that concept is. The idea that my recent scratching of my chin first acquired the 'present' property and then lost it is incoherent. |
| 23007 | The B-series can have a direction, as long as it does not arise from temporal flow [Baron/Miller] |
| Full Idea: The view that time has a direction is entirely consistent with the B-theory of time, as long as time's having a direction is not a matter of it having temporal flow. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.5) | |
| A reaction: I'm not sure how you could account for an intrinsic direction to time if it is not because of the 'flow'. The B-series seems to invite a reductive account of time's direction (e.g. to entropy). |
| 23003 | Static theories cannot account for time's obvious asymmetry, so time must be dynamic [Baron/Miller] |
| Full Idea: One argument for the dynamic theory of time is that time is, obviously, asymmetric, and as static theories can't account for this asymmetry, we ought to posit temporal passage to explain it. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5) | |
| A reaction: The B-series view (unlike the C-series) asserts that there is an order from past to future, but it offers no explanation of that fact. Physicists love to tell you the order could be in either direction, But why an 'order' at all? |
| 23004 | The direction of time is either primitive, or reducible to something else [Baron/Miller] |
| Full Idea: Primitivism is the view that time has a direction, and that its having that direction is intrinsic to time itself. Reductionism is the view that time has a direction, but its having that direction is reducible to something else. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.3.1) | |
| A reaction: The general suggestion for the second theory is that time's direction reduces to some aspect of the laws of nature. I strongly incline to the primitive view. Something's got to be primitive. |
| 23005 | The kaon does not seem to be time-reversal invariant, unlike the rest of nature [Baron/Miller] |
| Full Idea: The laws of nature are time-reversal invariant, with the small exception of the kaon (a type of sub-atomic particle) | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.3.2) | |
| A reaction: If that fact about the kaon were very secure indeed, then that would mean the collapse of the claims about the time-invariance of the laws. Since time-invariance is still routinely asserted, I assume it is not secure. |
| 23006 | Maybe the past is just the direction of decreasing entropy [Baron/Miller] |
| Full Idea: We could say that what we call the past is just the direction towards (for instance) decreasing entropy, and the direction we call the future is the direction towards increasing entropy. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.3.3) | |
| A reaction: One problem is that locally entropy can sometimes go the other way, which would imply local pockets with a reversed time's arrow,. |
| 23010 | We could explain time's direction by causation: past is the direction of causes, future of effects [Baron/Miller] |
| Full Idea: An option for accounting for the direction of time would be to appeal to the direction of causation …to the future is the direction towards which there are effects, and the past is the direction towards which there are causes. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 5.6.2) | |
| A reaction: The obvious problem is that we can no longer pick out a cause by saying it 'precedes' its effect. It is not obvious what other criterion can be used to distinguish them (esp. given Hume's regularity account). |
| 22989 | Static time theory presents change as one property at t1, and a different property at t2 [Baron/Miller] |
| Full Idea: The static theory of time appeals to an 'at-at' notion of change, which analyses change as objects or events having one property at time t1, and a different property at t2. (The worry about this is that it describes variation, but not real change). | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.4) | |
| A reaction: I suppose observing a different property at t2 is observing the result of a change, rather than the process. But then the process might be broken down into micro-gradations of properties. Maybe only results can be observed. |
| 23020 | If a time traveller kills his youthful grandfather, he both exists and fails to exist [Baron/Miller] |
| Full Idea: It is surely true that if a time traveller travels back in time and succeeds in shooting his youthful grandfather then the time traveller both exists and fails to exist. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 8.2) | |
| A reaction: This is the best known paradox of time travel. It is a special dramatic case of making any change to the past. If the traveller kills his neighbour's grandfather, his neighbour should vanish. Moving a speck of dust could have enduring results. |
| 23022 | Presentism means there no existing past for a time traveller to visit [Baron/Miller] |
| Full Idea: A time traveller can only travel to a location if the location exists, But if Presentism is true then past locations do not exist, so time travel to the past is impossible. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 8.3.1) | |
| A reaction: Might a time machine actually restore the past time which had ceased to exist? Then the problem is the information needed to achieve that. |
| 22987 | The past (unlike the future) is fixed, along with truths about it, by the existence of past objects [Baron/Miller] |
| Full Idea: It is the existence of past objects that explains why the past is fixed, and why there are truths about the past, and it is the non-existence of future objects that explains why the future is malleable. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.3) | |
| A reaction: The authors label this view 'EntityNowandThenism', and it comes in a section on the 'Temporal Ontology'. |
| 22990 | The moving spotlight says entities can have properties of being present, past or future [Baron/Miller] |
| Full Idea: The moving spotlight theorist maintains that there are special temporal properties that entities possess, namely the properties of being present, being past and being future. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 1.5.3) | |
| A reaction: Are these thought to be intrinsic properties of the objects, or (more plausibly) relational properties, between objects and times? Either view is weird. Does some godlike part of time scurry along, illuminating things, like a mouse under a carpet? |
| 22997 | The present moment is a matter of existence, not of acquiring a property [Baron/Miller] |
| Full Idea: Rather than treating presentness as an acquired property …. presentism equates the metaphysical specialness of the present with existence. | |
| From: Baron,S/Miller,K (Intro to the Philosophy of Time [2019], 2.2) | |
| A reaction: It seems like common sense to say that the recent scratching of my chin came into existence and then went out of existence (rather than that it acquired and then lost a property). |