We feel time pass: or do we?
Philosophers have long worried about the nature of time itself, and about our experience of time. While there’s practically nothing that all philosophers agree on, until recently there’s been almost complete agreement both that it seems to most of us as though time passes, and that that's why we report that it seems to us that way. You might wonder: what does it mean for it to seem to someone as though time passes? That’s a good question, to which there is no easy answer. Very roughly though, the idea is that it feels as though the future is coming towards us, and the past is receding away from us. So in some sense it feels as though time itself is moving, in that events that are currently in the future feel as though they are coming ever closer to us, becoming present, and then receding ever further into the past.
This might seem like a pretty benign assumption to make about how things seem. But, as with all things in philosophy, it turns out that the assumption is not so benign after all. That's because many philosophers working on the nature of time think that time is not like that at all: they deny that there is any sense in which future events come ever closer to us, become present, and then recede into the future.
They reject this picture of the world largely because it fits poorly into the scientific picture of time that emerged after Einstein’s general and special theory of relativity became widely accepted. These philosophers deny that time passes, or at least, they deny that it passes in anything like the way just described. At best, they think, time passes in some very flat footed and unexciting way, in that one moment is before another, and after yet another. Time itselfdoesn't pass, because there’s no one moment that really is present, so that which moment that is, changes. Moments don't go from really being future, to being really present, to being really past. Instead, to talk of past, present, and future, is not to talk about something objectively out there in the world, in the structure of time itself. Instead, it’s just to talk about where things are, relative to oneself: future things are things in one temporal direction from oneself, and past things are in the opposite temporal direction from oneself. But what is future relative to me, is past relative to someone else: nothing is just past, or future, objectively speaking.
So if it does seem to each of us as though time passes, we’re faced with having to say that the way things seem to us is a pervasive illusion. If, for almost all of us, at all times, it seems as though time passes, then we are all, always, suffering under an illusion. This is just what many philosophers have thought: the world seems to us a way that it is not.
Other philosophers deny that we are subject to such an illusion, but that’s because they hold that time really doespass. These philosophers have to explain how we can reconcile a metaphysical picture of the world, which contains temporal passage, with what science tell us about our world.
The point is that neither of these views looks very attractive. One view says that the world is as it seems to us, and that somehow contemporary science has gotten things wrong. The other view says that we are all constantly suffering from an illusion.
In light of this, a team of us from the University of Sydney recently took up the question of whether it really doesseem to people as though time passes. Of course, that’s a difficult question to answer, because the only access we have to how things seem to other people is what they say about their own experiences. So we began with an easier question to answer: do people report that it seems to them as though time passes. If people report that it seems to them to be that way, this is some evidence that it does seem that way. Of course, people can be wrong about the ways things seem to them. That’s because people can misdescribe their experiences in certain ways. Still, it seems safe to say that if people don’t report that it seems to them as time passes, this is reason to be sceptical that it really does seem that way to people.
So we ran an experiment. We showed hundreds of participants a whole lot of sentences about how things seem, and asked them whether or not they agreed or disagreed with the sentences (on a scale of 1-7). For instance, we asked people whether they agreed, or disagreed, on a scale of 1-7, with the sentence “it seems to me as though the future is coming closer”.
Here’s what we found: despite it being a nearly universal assumption amongst those investigating time and our experiences of it, that people will report that it seems as though time passes, or almost all the sentences which describe time moving, the average responses of participants were in the mid-range between 1 and 7. That is to say, people neither strongly agreed, nor strongly disagreed, that things seem to them that way. This was true for all of the sentences we presented, which described time moving.
This leads us to think that we need a new approach to investigating the connection between physics and our experience of time. Rather than assuming that either contemporary physics must be mistaken, since it’s not consistent with the way things seem, or assuming that we must all be suffering under an illusion, instead our results suggest that people don’t report that it seems as though time passes. That suggests that it probably doesn't seem that way to them. So there is no reason to think we are all suffering under some illusion. Instead, it’s much more likely that the way things seem to us, is entirely consistent with the kind of view of time that emerges from contemporary physics, a view that makes no room for temporal passage.