The Problem of Time
Berkeley has astonishing views about time. These views are relevant to our understanding of his position that sensible things (such as tables, trees, colors, and sounds) exist independently of our own perception of them.
According to Berkeley, time is nothing more than the succession of ideas in a specific mind. As a consequence, it would see that time is relative to particular minds, since Berkeley also thinks that the rate of succession (i.e. the rate of time flow) can vary depending upon the person. Additionally, Berkeley denies that God undergoes any change at all, and consequently does not have a succession of ideas in his own mind. In this way, God is outside of time.
Berkeley uses this account of time to solve a particular problem. Descartes had identified the essence of mind with pure thinking. Because of this, it followed that a mind had to always think in order to exist. But what happens when we are sleeping? Descartes had to say that the mind continues thinking even then (we just don’t remember). Locke thought this was absurd. He found it obvious that when we are sleeping, most of the time we are not thinking. For this reason, he denied that thinking was the essence of mind. Instead the sheer ability to think (along with the ability to move body) was a defining feature of mind. So obviously, a mind could exist even when it was not thinking.
Berkeley wishes to agree with Descartes insofar as minds must actually think in order to exist. So what happens when we are sleeping? Berkeley’s answer is that since time is subjective in this way, no time passes. When I am sleeping, I am not thinking, hence there is no succession of ideas, and hence no passage of time.
This seems to raise a host of problems. First, in Berkeley’s view, the tree can continue to exist even when I don’t perceive it since it can exist in the mind of God. But what about when I am sleeping? Time doesn’t pass then. So it doesn’t even make sense to say that the tree continues to exist “then” (when?). And insofar as it exists in God’s mind, it can’t be in time at all since God isn’t even in time.
Second, how is any kind of intersubjectivity possible at all? If time is relative to the individual, then how can we coordinate our activities? Berkeley says that so long as time-words apply in ordinary contexts and help us get through the day, all will be well. But if there is no such thing as an objective time-line, then we seem to be heading for trouble and “speaking with the vulgar” doesn’t seem to help.
Third, if time does not pass for me when I am sleeping, then surely time did not pass before I was born. (After all, for me time is just the succession of ideas in my own mind). So how could God have created the world? How could the Mosaic account of creation be correct? Obviously, Berkeley believes the biblical events are historical events. But how can he believe in historical events before his own birth at all?
In order to answer some of these worries, consider another obvious problem:
Berkeley says that the rate of time-flow can vary for each person. But what sense does it make to say that time flows faster for one person than another? Is the succession of ideas faster for one person? Are there more ideas per minute? (i.e., can I experience ideas at a rate of 10 per minute, while you experience ideas at a rate of 50 ideas per minute?). If so, does the measurement of the rate of time-flow not require objective time-units (minutes, etc.) for measurement? If so, does time not need to be something more than the mere subjective succession of ideas (so we can measure such successions by the minute)? Is Berkeley not, therefore, wrong?
First, in the model discussed above, the greater the succession of ideas (i.e. the more successive ideas I perceive), the faster events seem to occur (it’s as if the movie projector sped up). However, in Berkeley’s view the faster time flows, the slower events move along and longer they take. So the preceding way of measuring rate of time-flow (i.e. succession of ideas per minute) cannot be correct.
Instead, we can measure the rate of time per objective event. Imagine the following objective event (which we could all perceive): A dog runs across the street. Now suppose that for me, time elapses more quickly (i.e. there is a greater succession of ideas, such as internal thoughts in my mind) than there is for you. Then for me, the event will seem longer (i.e. be longer) since more subjective time has elapsed. Time will elapse more quickly, which is to say there has been “more of it” per objective event. Thus, it takes longer.
Well, it’s a nice idea. But there’s also a big problem. What about these so-called “objective events”? What are they? Where do they exist? In God’s mind? But God himself doesn’t have any succession of ideas.
I think that there is a way in which we can speak of public events, such as the coming to be, the changing, and the ceasing to be of public ideas. For example, consider the sound of thunder or the flash of lightning, or the visual rising or setting of the sun. First some light comes into existence. Then it goes away. Then some sound comes into existence. Then it goes away. Or else there is a sequence of visual ideas which gives the sense of the sun rising up into the sky, and then later on setting. Ideas like this can be placed in a kind of order in the mind of God. But just because God has ideas which are placed in a particular order does not mean that God himself experiences the succession. After all, ideas can be spatially ordered (left to right, right to left, etc.), ordered in terms of size, and there are also numerical orderings, and so forth. So God can have these ideas in a kind of order. And this ordering of public ideas can constitute the various events which Berkeley describes as “the course of nature.” That is, if you will, the history of the natural world.
Well, it’s a nice idea. But there’s still a big problem. In allowing the entire “course of nature” to exist in the mind of God, have we not made sense of time in a way as an objectively ordered sequence of events? And is this not to abstract time from the original, subjective “succession of ideas” which Berkeley alleged it to be?
Berkeley can say that this temporal ordering of events is not what we actually mean by “time”. What we must mean by “time”, for Berkeley, is this flowing - the movement of events from the future into the present and then into the past. If this movement of time, this passage of time, is essential to it – then the ordering of events in God’s mind while constituting something like a temporal sequence, does not itself constitute time. Rather time is the entrance and disappearance of those ideas into a specific finite mind.
At any rate, trees can exist independently of me (even when I am sleeping), in the mind of God since at least the tree’s existence will be part of the objective course of nature. Moreover, the duration of the tree can be measured in terms of public time units (e.g. one hundred years). However, actual time, for Berkeley, is the succession of ideas in a specific mind. Thus the same life of a tree (lasting one hundred years) will have a different duration depending upon who is perceiving it. When I am asleep, we can say that the tree continues to exist and ages eight hours. However, I do not witness that time (i.e. I do not exist during this time period). Yet this does not lead to a gappy existence of spirit. This is because the time period during which I don’t exist has absolutely no duration for me. There is NO succession of ideas.
One important lesson from this discussion is that spirits and ideas are related to time in very different ways. Some of the ideas which exist in the mind of God are ordered in a particular way (thus constituting the course of Nature). This ordering determines the sequence of coming to be and passing away of public ideas. Ideas are “created” when God, by divine decree, makes them perceivable to us. At any rate, different finite spirits can share a time-line in the sense that they can both witness the same public event. In this way, ideas constitute the course of nature which spirits are not a part of. Rather, spirits witness the various ideas which comprise the course of nature.
However, the rate of time flow can vary depending upon how many other ideas appear and disappear for a particular mind during that public event. The subjective appearance and disappearance of ideas in a mind is the flow of time. In this ways, finite spirits are individual “centers of time” (whenever a spirit perceives, it is “now”).