The Nature of Time

Buddhism doesn’t regard time as an absolute container in which events occur and exist, somehow independently of these events. It’s not that space and time are some sort of background grid that provides the space-time coordinates of objects located in it and the objects can just move from one place to another as if they were on some sort of grand four-dimensional chessboard. It’s also not something that is sort of there and passing as if time were an entity that is moving and passing. Time in Buddhism is a nonstatic phenomenon that is neither a form of physical phenomenon nor a way of being aware of something (ldan-min ’du-byed, non-congruent affecting variable). Nonstatic means that it changes from moment to moment, and it is an imputation phenomenon on a nonstatic continuum. An imputation phenomenon is one that exists inseparably on a basis, like a whole and parts, or the age of something and that something. No one has to impute it – in a sense, it is just there.
More specifically, time in Buddhism refers to an interval on an individual mental continuum between the experience of two sequential events. Since mental continuums have no beginning and no end – and thus time as well has no beginning and no end – the two events may not necessarily both occur in one lifetime. A period of time, then, is not something that exists independently of the two sequentially related events or a person’s experiencing them. 

Since a period of time is formulated in terms of an experience of sequential events, time is a function of, and therefore relative to, the mind that experiences it. Furthermore, we can cognize a period of time through a category, such as a “day,” and a word, like “day,” or a name, like “Wednesday.” Cognition through the mental label of a category and the designation of a word or name are types of conceptual cognition and they too are relative to a person’s mind within the context of its conceptual framework and vocabulary. 

A period of time, then, can be cognized both non-conceptually and conceptually. When we see a sunrise, this is non-conceptual cognition. We are non-conceptually seeing not just a sunrise, but also the first moment of the period of time that will extend to the next sunrise. Seeing this first moment of the sequence of moments until the next sunrise is not optional when seeing that sunrise. What is optional is cognizing the sunrise conceptually through the category and word “day” or “Wednesday.” 

A mind may have different concepts of periods of time and different words for them, but even without them, such as in the case of the mind of a fly seeing the sunrise, the fly still sees, non-conceptually, the first moment in the sequence of moments until the next sunrise. This means that even if we stop conceptually cognizing time through a category and word and enter into a totally non-conceptual state, it would not render the interval between two sequentially connected events nonexistent, either objectively or subjectively. We would still experience periods of time. 

In short, just because a temporal interval is conceptually knowable through names and concepts, this doesn’t mean that time is just a conceptual phenomenon. Time is conceptually knowable, but that doesn’t mean that it exists only when somebody mentally labels it with a category or designates it with a word, nor that time or a temporal interval can only be cognized conceptually.

From a Gelug point of view, we certainly do cognize time non-conceptually. It’s a nonstatic phenomenon. It’s neither a way of being aware nor a form of physical phenomenon, and so time is validly knowable non-conceptually. Conceptually means “through a category.” When we see a glass fall from the table and break on the floor, we don’t just see a sequence of still frames, like a strip of a movie film, and then conceptually synthesize them into an event (although some Buddhist schools say that, for example, the non-Gelugpa schools). According to the Gelug explanation, simultaneously, as we see the glass in each of the different locations as it falls, we’d have to say that we also see the falling of the glass, the impermanence of the glass, and a moment in the interval between when it falls from the table to when it hits the floor. This is despite the fact that the falling of the glass, the moments during the period of time that the glass falls, and the impermanence of the glass are not forms of physical phenomena. They are what are known as “imputedly knowable phenomena” and they are knowable simultaneously with seeing the glass as it falls.  

This Gelug explanation is one that fits more with common sense: We do see a falling. We do see somebody running. We don’t just see still frames, do we? Now, how all of this fits in with brain physiology, I don’t know. Do you have any idea, Jorge? Isn’t it that it takes a certain duration of very tiny moments for the brain to actually build up a picture of what’s happening?

Dr. Jorge Numata: The absolute minimum would be – like in Francisco Varela’s work – the time of the processing of a neuron, which is less than a millisecond.

Buddhism would say something similar. It explains this in terms of one sixty-fifth of a finger snap. However, it doesn’t matter what the measurement of it is. The point is that from this Gelug point of view, we do actually see the falling of the glass. We also see that it is impermanent; we don’t just conceptualize that through the category of impermanence. We don’t have to give it the name impermanent; we don’t have to say in our head “falling,” nevertheless, we can see it. Like that, time, meaning a period of time, is an imputation phenomenon on the moments during an interval between a cause and an effect. For example, the glass leaves here, and the effect is that it reaches the ground and breaks; it can be seen non-conceptually.

One thing that I also read from studies that Francisco Varela did is that it seems there’s a limited temporal resolution that the brain can really process, so things that happen in very close proximity to each other are perceived as happening simultaneously. This would be more like putting things into steel frames on a very low non-conceptual basis. I don’t know. Also, we’re not like a movie camera that has only one piece of hardware that captures everything. The brain processes signals in many different parts. For example, shapes are processed in one place, and colors are processed in another. Thus, this movement wouldn’t be processed in just one central place. This processing could also have different timescales and resolutions, but we perceive it as happening smoothly. In the end, we perceive it as movement. It’s hard to say if it’s conceptual or non-conceptual from a Western physiological point of view. Conceptual has to do with categories. For instance, when we give a name to this object, table. Well, it is an item that fits in the category of table. There are a lot of other items that can also fit into the category of table. It’s seeing it in terms of a category; that’s conceptual.

As we established, we can cognize a period of time both conceptually and non-conceptually. Impermanence, nonstaticness, or change implies cause and effect. If something changes, it implies cause and effect, and a sequence of cause and effect implies time, namely a period of time. Right? Although voidness is a static phenomenon, and it’s the deepest truth about everything (it’s the fact that nothing exists in impossible ways, so it’s the absence of impossible ways of existing), and it’s not subject to cause and effect (it’s just a fact that is always true, that’s always the case), nonetheless, that doesn’t mean that the deepest truth about everything is that everything actually exists independently of time.

We have such an assertion in some of the non-Buddhist Indian systems, that time and space are just an illusion, and when we gain liberation, the atman, or the soul, exists outside of time and space. If we saw the deepest truth (that space and time are just an illusion), then we would be freed from the constrictions of it. However, that’s not Buddhism. When we see the deepest truth about things, it’s not that we are then liberated from time and space; it’s not like that at all. If everything existed independently of time and space as the deepest truth about it, then there’d be no cause and effect, and there would be no liberation because liberation couldn’t occur through a causal process of a spiritual path. It doesn’t make any sense that, somehow, we can get out of space and time.

Likewise, if we approach the deepest truth in terms of it being beyond the categories of truly existent and truly nonexistent, both or neither (that it’s inexpressible), this still doesn’t make time totally nonexistent, right? It’s not that the deepest truth is beyond time and space. However, time, like all validly knowable phenomena, exists devoid of impossible ways of existing. That’s the deepest truth about it, which means it doesn’t exist as some absolute thing independently of everything else. Periods of time exist; they actually do exist, but how do we establish that they exist? According to the Gelug Prasangika assertions, we can establish that they exist only by the words or concepts for them. This is the way that we’ve been explaining voidness for a long time here. In other words, what is time? What establishes that it exists is just the words for it. It’s the referent object of the words or concepts for it that can be mentally labeled and designated conceptually on a sequence of cause and effect.

In other words, the existence of a period of time cannot be established from the side of that sequence of cause and effect. Where is it then? Is the time in the cause? Is it in the effect? Is it somewhere in between? We can’t establish its existence in that way – that’s impossible – as if there were an absolute thing, like a background. However, what establishes that it exists? When we have the word or concept time, what is time? Time is exclusively only what the word time refers to, but we can’t actually point to it or find it. For those who are not familiar with all the voidness discussions, this is admittedly really difficult to understand. For those of us who have a little bit of familiarity, time exists in the same way as everything else that’s validly knowable.

So, time does conventionally exist. The deepest truth about it is that it doesn’t exist in impossible ways. Impossible ways would be as an absolute container somewhere in the background or as something that we could exist independently from. These are all impossible. Time is not absolute. It’s not something that’s merely an illusion, although it is like an illusion in that it cannot be found. 

Then, what is time? Well, we can’t actually find it anywhere. Although we can know it validly, we can’t point to it. All that we can say is that it’s an imputation phenomenon on a sequence of cause and effect, and it’s merely what the word time refers to, whether we talk about a year or a month or a moment or whatever. That’s the only thing that we can say can establish or prove that it exists. Nevertheless, that doesn’t make it exist. Labeling it doesn’t cause it to exist.

There are several views about time, meaning a period of time, in the different Indo-Tibetan traditions of Buddhism. In all the Buddhist systems, however, a period of time is an imputation phenomenon on the mental continuum of a person’s moments of cognition during the interval between their experiencing of two sequential events, such as their committing a karmic action and their experiencing the ripening of its results. It is an imputation phenomenon on the basis of each of the moments in that portion of the mental continuum. Since the experience in each of those moments is different, so too the time experienced in each moment is different – one moment after the committing of the cause is no longer happening, two moments after it, three moments after, and so on. In this sense, time is nonstatic. It is continually changing and appears together with the objects of non-conceptual sense cognition at any moment during the interval between two events.

When we speak about the conceptual cognition of time  – how we conceive of time – we get into the realm of the conceptual frameworks or concepts with which we not only label periods of time, but also how we measure these periods, in terms of days, weeks and years. In a sense, a period of time is like a distance measured in the dimension of time, between two points on a specific individual’s mental continuum. Do you follow that? Here we can conceptualize it a little bit that way.

Buddhism, then, does not speak about time as a thing that passes, but rather we can think of time in terms of temporal intervals. Right? Temporal intervals, like a year, are nonstatic since we can experience them from moment to moment, and each moment that we experience the year is different, isn’t it? Think about that. We don’t experience the whole year at once, although we can think about the whole year, and obviously, we can think about it conceptually and sort of in a sense summarize the whole year through a category of the year, and many things that happened during the year. However, we experience the year moment to moment. It changes from moment to moment. Keep in mind, though, it’s not a form of physical phenomenon, and it’s not a way of being aware of something. It’s a little bit more abstract, isn’t it, but not abstract in the sense of being vague.

A temporal interval on a mental continuum can be specified in terms of karmic sequences, such as the interval between somebody acting destructively and the same person’s experiencing unhappiness and suffering as a result that ripens from it. Or a temporal interval can be specified in terms of cognitive sequences on someone’s mental continuum, such as the interval between somebody seeing a leaf falling from a tree and then seeing the leaf on the ground. That’s also a type of causal sequence that occurs on a mental continuum. In most Buddhist systems, but not all, time is also a nonstatic imputation phenomenon on the basis of a continuum of a nonstatic external object that’s undergoing change according to the laws of cause and effect, like what we were just talking about, the continuum of the leaf falling from a tree, or on the continuum of a pot of milk transforming into a pot of yogurt and that transforming into a pot of cheese.

Actually, those are quite different examples, the leaf falling from the tree and the milk changing into yogurt and that into cheese, but we won’t go into that. That’s a very large topic that is discussed in terms of transformation. Is it one thing that is transforming? In the case of the leaf, it might seem fairly obvious that the leaf is just transforming from being here to being there. What about when the milk transforms into yogurt and the yogurt into the cheese? Is there something that has transformed and just changed its nature, its function, or its form in three different phases? That’s a very complicated and full topic. There are four different positions in the Vaibhashika school of Buddhism, but we won’t go into that. Actually, I discussed that in the lecture I gave about time that’s on my website.

[See: The Nature of Time as a Temporal Interval.]

Let’s restrict ourselves, then, to discussing time simply in terms of the intervals between events on an individual’s mental continuum since those are the most relevant to the Buddhist path of gaining liberation from karma, the results of karma, and so on. It’s clear that, in this context, time is relative to and dependent on the observer, both from the point of view of the observer’s experiencing two events (a karmic cause and an effect) and an observer’s mentally labeling both the events and the interval between them.

As an observer, do we even have to notice such an interval? Do we even have to make the connection between a cause and an effect in order to experience the interval between the two? Well, no, we don’t. That’s why I was saying that we don’t have to actually mentally label it – but it could be mentally labeled – and we still experience it. 

Again, we have to keep in mind that time is a nonstatic phenomenon. It’s neither a form of physical phenomenon nor a way of being aware of something. This means that a period of time, that interval, is not the same as a person’s subjective perception and conceptualization of a period of time. Those are ways of being aware of something. Our experience of time is different from time. How we regard time is different from time itself. For most people, the interval of a year, for instance, seems much shorter as they grow older. A year seems to pass more quickly at age forty than it does at age four. Why is that? It is true, isn’t it? A year seems much longer when you’re four years old than when you’re forty or when you’re sixty.

Well, the reason for that, I think – it’s not explained in the texts – is because one year is 25% of the life of a four-year-old and it’s only 2.5% of the life of a forty-year-old. Because it’s a much larger percentage of our life, it seems to take much longer to pass. Then again, is it still a year? Being a year has nothing to do with – not that it has nothing to do with it – but it’s a separate issue from our perception of a year. Perception is a way of being aware of it. A year is not a way of being aware of something. Okay? Do we need a moment to digest all of this? Maybe that would be useful.

I think it is quite important to overcome or dismiss the misconceptions that we might have about time. When we think of time as something that passes, and it can pass more quickly or more slowly for us, what is the misconception behind that? The misconception is that time, like space, is a background grid and that just as we can move from one point in space to another more quickly and the location passes or changes in terms of our perception of it, similarly, the same is happening with time. The misconception is that there’s time sitting somewhere over there, and we’re running past it, or we’re staying stationary and it’s moving past us; therefore, it seems as though time is something in the background that’s passing, and it passes more or less quickly depending on our age. However, that’s a misconception; that’s not the way it is, but it might feel like that.

That’s why when we speak about voidness in Buddhism, we’re talking about identifying what’s impossible and saying that there is no such thing. That’s what voidness is saying: There’s no such thing; it doesn’t exist like that. Remember, the main reason why it doesn’t exist like that is because then there couldn’t be cause and effect, and what we do would be something separate from that background – we could be separated from that background (it would be there whether we’re there or not). It can’t be that time and space are some absolute, like a grid in the background, and that it moves, or we’re moving through it, so that it passes.

Since time can be mentally labeled with measurements on a nonstatic continuum, whether an internal or an external one, the units with which it’s measured are relative and merely convention. Then, how do we measure it? What are the units of measurement? A specific interval can be labeled by one individual in many different ways, depending on the conventions he or she follows.

Years

Take for example the label a year. What is a year? A year is usually measured in terms of the spatial movement and position either of heavenly bodies or of the persons measuring a year. That raises the topic of the relation of time and space, doesn’t it?

The starting of a new year is a good example of this.

Yes, the start of a new year is totally arbitrary. There are so many different calendar systems that have the new year starting at a different time. However, what about the interval of a year itself? This is what I’m speaking about. It’s usually measured in terms of the motion of something, which is very interesting in terms of showing us the relation between space and time. Of course, physics would say there’s a very integral relationship.

Usually, there are two types of years:

• There’s a solar year. It is the temporal interval measured according to one revolution of the earth around the sun. Traditionally, this was measured from the perspective of the earth according to the passage of the sun through either 12 signs of the zodiac or, in Indian and Chinese systems, 27 stations of the moon (where the moon is in successive parts of its phases). These signs of the zodiac or stations of the moon are actually galaxies other than our own Milky Way. There’s something in the background, as it were, from our perspective of our earth and sun. The sun orbits around the center of the Milky Way galaxy, and the other galaxies are moving in different ways. They appear stationary from our point of view, but because of that, the interval between successive times a certain galaxy appears in the background behind the rising sun will differ each year. It’s because of that that we have things like leap days and leap years and these sorts of things. The interval of a year isn’t constant in terms of the solar year. 

• Then, we have a lunar year. A lunar year is measured according to 12 cycles of the phases of the moon. In other words, from new moon to new moon, or full moon to full moon. Twelve of those are counted as a year. That interval also varies from year to year since new and full moons depend on the position of the sun relative to the position of the moon. When the moon is between the earth and the sun, it’s the new moon. When the moon’s on the other side of the earth, it’s the full moon. The interval of the new moon will occur when the sun and the moon are, from our perspective on the earth, together at the beginning of one constellation (let’s say Aries), and then it has to go all the way around from our perspective on the earth to the next galaxy (Taurus), when the next new moon will occur. Of course, that’s going to vary over many, many years – each month will be slightly different, and each year will be slightly different. 

Also, one person can label 12 cycles of phases of the moon a year, but the same person or somebody else could label it less than a year if the same period is measured with solar years. A lunar year is not the same as a solar year. We have a period of time, and we can measure it by lunar years, or we can measure it, the same period of time, with solar years; in one case, it will be a year, and in another, it will be less than or more than a year.

Now, let’s bring in science. From a relativistic point of view, the interval of a year is relative not only to the counting system that somebody uses for measuring it, but it’s also relative to the speed at which the person is traveling, on whose mental continuum it’s measured, isn’t it? There’s a year specified in terms of the motion of the speed of somebody and also in terms of the speed of somebody else measuring it. I mean, we can measure our own time, but something else could also measure our time.

Then, what’s a year? For example, the closer the person travels to the speed of light, the longer the duration between the person’s 29th and 30th birthdays would be when measured by somebody traveling at a slower speed. All right? Recall, we’re not talking here about the experiencing of the two birthdays by the two people traveling at different speeds. That’s a way of being aware of a year. We’re talking about the actual interval between the two birthdays, which could be labeled a year. One interval, from the point of view of the person who’s traveling near the speed of light, will be a year between the 29th and 30th birthday. When measured from the point of view of somebody moving slower, it will be much longer than a year.

Days

If we consider one interval being called a year, is there an objective interval that’s being labeled differently by one person or by two different persons even if they are at the same location and traveling at the same speed relative to each other? This really gets to the heart of the matter. Is there actually a year that is happening and different people measure and experience it differently, or is it actually different to different people? Is there some objective year?

Now, if there were such an objective interval of time, it would have to be something labeled on parts, such as a certain number of days, wouldn’t it? The labeled days, however, could have different definitions, depending on how they’re measured. For example, there are three types of days discussed in Hindu and Tibetan astrology, depending on how we define “day”:

• A day can be a solar day (nyin-zhag). This is the temporal interval from one dawn to the next. This interval, though, is relative to the person’s position on the planet and will vary over the course of a year, as dawn occurs later each day after the summer solstice and earlier each day after the winter solstice. Each solar day is actually a different interval, although it’s called a day. Then, we have a year being a certain number of such days. Well, is a year different for a certain number when measured at a different location? It becomes a very interesting question. 

• Then, a zodiac day (khyim-zhag). A zodiac day is the temporal interval between the sun being located, from the perspective of the earth, at one degree and then the next degree in the course of its movement around the 360 degrees of the zodiac. This was used very much in ancient times in astrology. We divide the heavens, the course that the sun goes through, into 360 degrees, and a day is the time it takes for the sun to go from one degree to the next degree over the course of a year, right at a certain time. These intervals also vary over the course of a year since the orbit of the earth around the sun is an ellipse, and so the speed of the earth varies as it orbits the sun. In the Tibetan astrological calculations, we have to correct for different speeds. What a zodiac day is and how long it is becomes a variable. Is there some definite length, though, that is behind all of this? That’s the interesting question. 

• Next, we have a lunar-date day (tshes-zhag), which is correlated with the phases of the moon. If we divide into 30 equal portions the distance, relative to the zodiac, between the position of the moon at one new moon and the next new moon, with these different phases of the moon, what’s going to be in the background is a different constellation. Then, a lunar-date day is the temporal interval between the moon being located at one-thirtieth the portion of that distance and the next (that’s how we get months, by the way). Such days also vary over the course of a month and a year, again because the moon’s orbit around the earth is an ellipse and the earth’s orbit around the Sun is an ellipse (so the speeds are going to be different at different times of that orbit). This also changes everything and makes it a variable. 

These are the very varying types of days with which we would measure what a year is, because a year, as a whole, is an imputation phenomenon on these parts.

In the West, we have a clock day, which is the temporal interval from the halfway point between one sunset and sunrise to the halfway point between the next sunset and sunrise. However, sunrise and sunset, of course, are labeled in terms of the position of the sun relative to the east and west horizons of the person observing them. The halfway points don’t vary over the course of a year, but they’re relative to one’s location. What happens when we’re at the North Pole and the sun doesn’t set? This becomes a problem, how we would actually calculate the start of a day. So, these are our Western clock days.

Hours

Further, a day is an imputation phenomenon on hours. Is there a certain absolute number of hours that are being measured by the different labels of a day? No. The 24-hour day, for example, was invented by the ancient Egyptians, and it went from the Egyptians into the Hebrew calendar and into the Greek and the Roman calendar. For all of them, a day was a solar day (if we remember, a solar day is from dawn to dawn), and the 24 hours was a division of a solar day. The day and night were each divided into 12 hours, from dawn to dusk and dusk to dawn, so the length of an hour, being one-twelfth of the day or night, varied according to the season and the length of daylight, and whether it was an hour of the day or the night, and also according to our position on the planet. If the day was much, much longer than the night, one hour of the day was much longer than an hour of the night. What would be the hour if we were further north? That would also change. That makes it very difficult to coordinate military movements, doesn’t it, if we say we’re going to have the invasion at a certain time.

Hindu and Buddhist astrology divides the day and night, from dawn to dusk and dusk to dawn, each into six, not 12 hours. A standard-length hour with 24 such hours in a day was not adopted in Western Europe until the end of the 13th century with the invention of mechanical clocks. It was only at that point that we got a standard-length hour. Of course, if we travel at different speeds, what is the standard-length hour? 

That’s solar days. If we talk about these zodiac and lunar days in Hindu and Buddhist astrology, they divide them into 60 hours. Then, how many hours are in a day? Twelve hours, 24 hours, or 60 hours? What’s an hour?

We could apply the same type of analysis for minutes and seconds. Then, we would get into this whole discussion of the relation of the whole and the parts. Is there an ultimately smallest part? Further, if all these parts are variable, what in the world is going on here? Is there some sort of absolute interval of time that can be called a year, a day, an hour, a minute, or a second? What about atomic clocks? They use as a standard of measurement the intervals on the atomic resonance frequency of cesium. Is that absolute, or doesn’t that also vary depending on the speed the cesium atom is moving (for instance, if we had a cesium atom on a starship going near the speed of light)? Even that will vary, won’t it?

Also, gravity has an influence. If we have this atomic clock in an airplane, where gravity is slightly less than down on earth at sea level, then there’s already a measurable effect, a measurable difference in the number of cycles that we have here on earth and up there in an airplane. We’re further away from the earth, and so gravity is less strong.

Right. Gravity also affects time, an interval of time in the vibration of the radio frequency of a cesium atom. I think I remember reading about an experiment at Harvard where they measured the time something took _ I don’t recall exactly what – at the top and at the bottom of a tower, and there was a micro-micro-microsecond difference. Then again, what were they measuring it based on? Is there a standard?

You’re just counting it at the top of the tower and then bringing it back down. Or I don’t know. Yeah, of course, that’s the problem. You don’t have an absolute time.

That’s the problem. That is exactly what we’re talking about here, that there is no absolute time. 

You’re comparing one thing to another. You’re comparing one length of time to another length of time. There’s no absolute.

Is it that we’re comparing one length of time to another length of time when we’re talking about measuring? Or is there an actual interval between a cause and an effect that we're measuring? Yes, there is an interval. Well, how long is that interval (we’re not talking about our individual experience of the interval)? This is the question. It brings up the whole topic of a common-denominator (gzhi-mthun) temporal interval that serves as the basis for labeling by different persons and with many different labels of temporal units. Further, that gets into the whole discussion of external phenomena and the Chittamatra-Prasangika difference here, but that I think can wait till our next session.

What is a common denominator?

A common denominator is something that is common to many different things or many different systems, so it’s shared. It is something in one system and something else in another system. In this sense, it is common to both systems. 

Let’s just take a moment to digest what we’ve discussed so far, and we’ll have our coffee and tea break; then, we’ll get into this whole discussion of common denominators. That brings in the subject of external phenomena, which, of course, brings in the topic of the Chittamatra versus the Prasangika difference. Is there an actual externally happening year 2006 that different people are experiencing differently or not?