| 22957 | We can't tell whether the changing present moment is one thing, or a succession of things [Aristotle] |
| Full Idea: It is not easy to see whether the now, which appears to be the boundary between past and future, remains always one and the same or is different from time to time. | |
| From: Aristotle (Physics [c.337 BCE], 218a08) | |
| A reaction: [also 219b13] Presumably the A-series view suggests that each present moment is different, but Broad's moving spotlight analogy gives the impression of a single present instant moving through time. If the present is one, what sort of thing is it? |
| 22966 | The present moment is a link (of past to future), and also a limit (of past and of future) [Aristotle] |
| Full Idea: The now is a link of time, for it links together past and future time, and is a limit of time, since it is a beginning of one and an end of the other. | |
| From: Aristotle (Physics [c.337 BCE], 222a10) | |
| A reaction: It is not clear how a limit (such as the boundary between two overlapping bits of paper) can also be a 'link'. He noticed the problem in Idea 22958. |
| 20818 | The present does not exist, so our immediate experience is actually part past and part future [Chrysippus, by Plutarch] |
| Full Idea: Stoics do not allow a minimal time to exist, and do not want to have a partless 'now'; so what one thinks one has grasped as present is in part future and in part past. | |
| From: report of Chrysippus (fragments/reports [c.240 BCE]) by Plutarch - On Common Conceptions 1081c | |
| A reaction: [from lost On Parts Bk3-5] I agree with the ontology here, but I take our grasp of the present to be very short-term memory of the past. I ignore special relativity. Chrysippus expressed two views about this; in the other one he was a Presentist. |
| 20821 | Time is continous and infinitely divisible, so there cannot be a wholly present time [Chrysippus, by Stobaeus] |
| Full Idea: Chrysippus says most clearly that no time is wholly present; for since the divisibility of continuous things is infinite, time as a whole is also subject to infinite divisibility by this method of division. | |
| From: report of Chrysippus (fragments/reports [c.240 BCE]) by John Stobaeus - Anthology 1.08.42 | |
| A reaction: But what is his reason for thinking that time is a continuous thing? There is a minimum time in quantum mechanics (the Planck Time), but do these quantum intervals overlap? Compare Idea 20819. |
| 22742 | Socrates either dies when he exists (before his death) or when he doesn't (after his death) [Sext.Empiricus] |
| Full Idea: Socrates either dies when existing, or when not existing. …He does not die when he exists, for he is alive, and he does not die when he has died, for then he will be dying twice, which is absurd. So then, Socrates does not die. | |
| From: Sextus Empiricus (Against the Physicists (two books) [c.180], I.269) | |
| A reaction: A nice dramatisation of a major dilemma. The present moment is just the boundary between the past and the future, and so has no magnitude, and hence nothing can occur during the present. Perhaps my favourite philosophical dilemma. |
| 22751 | If the present is just the limit of the past or the future, it can't exist because they don't exist [Sext.Empiricus] |
| Full Idea: If the present is the limit of the past, and the limit of the past has passed away together with that of which it is the limit, the present no longer exists. And if the present begins the future, which doesn't exist, the present does not yet exist. | |
| From: Sextus Empiricus (Against the Physicists (two books) [c.180], II.201) | |
| A reaction: If I mark a line on the ground where the wall will begin, the limit seems prior to the object. The gun starts the race, but is not part of it. That said, I cannot think of any more mysterious entity than the present moment. It isn't a line or a bang. |
| 22891 | We could be aware of time if senses briefly vibrated, extending their experience of movement [Russell, by Bardon] |
| Full Idea: Russell suggested, in defence of an empiricist theory of time-awareness, that a sense organ goes on vibrating, like a piano string, for while after the stimulation. Thus we can see the movement of a second hand, seen in several places at once. | |
| From: report of Bertrand Russell (An Outline of Philosophy [1927]) by Adrian Bardon - Brief History of the Philosophy of Time 2 'Realism' | |
| A reaction: Hm. If they were vibrating the last experience, they couldn't pick up the new one. When something fast happens the brain resonates fortissimo! If your eyes are moving it will be different neurons that get fired at each instant. |
| 17552 | In relativity the length of the 'present moment' is relative to distance from the observer [Heisenberg] |
| Full Idea: In classical theory we assume past and future are separated by an infinitely short time interval called the present moment. In relativity it is different: future and past are separated by a finite time interval dependent on the distance from the observer. | |
| From: Werner Heisenberg (Physics and Philosophy [1958], 07) | |
| A reaction: Not sure I understand this, but it is a revelation to realise that not only is time made relative to observers, but the length of the 'present moment' also becomes relative. The infinitesimal present moment has always bothered me. |
| 18401 | The pure present moment is too brief to be experienced [Armstrong] |
| Full Idea: The metaphysical present will be a strict instant, or, if time is not infinitely divisible, the present will be a minimum granule of duration. But strict instants or minimal granules of duration, if these exist, cannot be experienced. | |
| From: David M. Armstrong (Truth and Truthmakers [2004], 11) | |
| A reaction: He points out that this is ironic, since Presentism lies on the basic experience of the present. |
| 12690 | The present is the collapse of the light wavefront from the Big Bang [Ellis] |
| Full Idea: The global wavefront that collapses when a light signal from the Big Bang is observed is what most plausibly defines the frontier between past and future. | |
| From: Brian Ellis (The Metaphysics of Scientific Realism [2009], 6) | |
| A reaction: I'm not sure I understand this, but it is clearly worth passing on. Of all the deep mysteries, the 'present' time may be the deepest. |
| 22942 | If time is infinitely divisible, then the present must be infinitely short [Le Poidevin] |
| Full Idea: Assuming time to be infinitely divisible, the present can have no duration at all, for if it did, we could divide it into parts, and some parts would be earlier than others. | |
| From: Robin Le Poidevin (Travels in Four Dimensions [2003], 09 'in present') | |
| A reaction: I quite like Aristotle's view that things only have parts when you actually divide them. In modern physics fields don't seem to be infinitely divisible. It's a puzzle, though, innit? |
| 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). |