Ten Ideas About Time
Here’s an interesting article positing ten “facts” about time, as understood from the point of view of a physicist, Sean Carroll. The ideas are taken from a conference, and attributions for the ideas are in the original article. I thought it would be interesting to see how each of these ten points reflects on time as conceived in Buddhism. Here goes:
1. Time exists. Might as well get this common question out of the way. Of course time exists — otherwise how would we set our alarm clocks? Time organizes the universe into an ordered series of moments, and thank goodness; what a mess it would be if reality were complete different from moment to moment. The real question is whether or not time is fundamental, or perhaps emergent. We used to think that “temperature” was a basic category of nature, but now we know it emerges from the motion of atoms. When it comes to whether time is fundamental, the answer is: nobody knows. My bet is “yes,” but we’ll need to understand quantum gravity much better before we can say for sure.
According to mainstream Buddhist philosophy, time does not in fact exist. Whether anything at all “exists” is debated (since things are interdependant, how can they truly be said to “exist”?) But time is even less secure than, say, matter or mind. Normally time is conceived of as merely the fluctuations in consciousness, and we speak of “time” as merely a convention to help in communication. I don’t think Carroll’s argument here, such as it is, is cogent at all: time “exists” because otherwise things would be in a mess? Not really. The observable reality is the activity of things (including the mind). An inferrable reality is that this activity is ordered (since, for example, we can observe repeated patterns of similar phenomena: day follows night, greed follows contact, and so on.) Time is no more than a meta-inference, an inference from an inference derived from our memory of changes in consciousness. I’m afraid that Carroll’s perspective is still based in a “cosmic policeman” view of natural phenomena: the laws of nature tell everything what to do. From a Buddhist point of view, this is nonsense. There is no “time” that structures events into past, present and future, there is just the observable reality, which we find useful to describe in terms of a concept of time.
2. The past and future are equally real. This isn’t completely accepted, but it should be. Intuitively we think that the “now” is real, while the past is fixed and in the books, and the future hasn’t yet occurred. But physics teaches us something remarkable: every event in the past and future is implicit in the current moment. This is hard to see in our everyday lives, since we’re nowhere close to knowing everything about the universe at any moment, nor will we ever be — but the equations don’t lie. As Einstein put it, “It appears therefore more natural to think of physical reality as a four dimensional existence, instead of, as hitherto, the evolution of a three dimensional existence.”
Classic Sarvastivada! I’m not sure how true this is even in the arena of physics – no doubt it is true for Einstein, but what of quantum ambiguity? In any case, see the rhetorical trick Carroll is using here: if the equations of physics don’t distinguish between past, present, and future (and remember, the equations don’t lie!), then there is no meaningful distinction. Except, you know, every waking moment of consciousness of every sentient being ever. (Caveat: due exception made for deep states of samadhi…) But we can just discount that, because, since when has real experience had anything to do with the truth? Facts within the realm of physics may be neutral regarding past, present, and future, but the mind certainly is not. There are genuine differences between these things, and any description of the world that takes consciousness seriously has to account for these. This is not to say that the classic Theravadin view (that the present is real and the past and future merely illusions) is necessarily correct. I think it is more subtle than that.
3. Everyone experiences time differently. This is true at the level of both physics and biology. Within physics, we used to have Sir Isaac Newton’s view of time, which was universal and shared by everyone. But then Einstein came along and explained that how much time elapses for a person depends on how they travel through space (especially near the speed of light) as well as the gravitational field (especially if its near a black hole). From a biological or psychological perspective, the time measured by atomic clocks isn’t as important as the time measured by our internal rhythms and the accumulation of memories. That happens differently depending on who we are and what we are experiencing; there’s a real sense in which time moves more quickly when we’re older.
In this we can agree. In fact, the relativity of time is a commonplace to any meditator. Have you noticed, on retreat the minutes last a lot longer, but the weeks just whizz by? As usual, this fact of meditative experience is reflected in Buddhist cosmology, where not only is the lifespan of higher realms said to be much longer, but the subjective experience of time is said to be far slower. The Payasi Sutta says, “In the Heaven of the Thirty Three Gods, time passes at a different pace, and people live much longer. In the period of our century, only a single day would have passed for them.”
4. You live in the past. About 80 milliseconds in the past, to be precise. Use one hand to touch your nose, and the other to touch one of your feet, at exactly the same time. You will experience them as simultaneous acts. But that’s mysterious — clearly it takes more time for the signal to travel up your nerves from your feet to your brain than from your nose. The reconciliation is simple: our conscious experience takes time to assemble, and your brain waits for all the relevant input before it experiences the “now.” Experiments have shown that the lag between things happening and us experiencing them is about 80 milliseconds.
This is one of those little details that is in retrospect obvious. Bits and pieces are assembled from experience, and these take different amounts of time to be processed into the “present”. In Buddhist psychology, the factor that does the assembling is called “saññā“. It is not that different from viewing a page on the internet, where all the different elements are passed in various pathways through the web and assembled by the browser on your computer. Notice how this notion of a “continually assembled” present doesn’t sit all that well with the commonplace Abhidhamma view of an instananeous “present moment”. Actually, the Buddha didn’t speak of a “present moment’, but of the “present” (paccuppanna rather than paccuppannakkhana). Reality as experienced is not a bunch of discrete lumps of immediately present flashes of awareness, but a continually unfolding, dynamically constructed, field of awareness.
5. Your memory isn’t as good as you think. When you remember an event in the past, your brain uses a very similar technique to imagining the future. The process is less like “replaying a video” than “putting on a play from a script.” If the script is wrong for whatever reason, you can have a false memory that is just as vivid as a true one. Eyewitness testimony, it turns out, is one of the least reliable forms of evidence allowed into courtrooms.
This is a commonplace, but it is interesting to know that the way the brain constructs the past and the future are similar. (There is some research into dreams that suggests that we dream approximately equally of the past and future…) Both of them are constructed realities. But hey! Haven’t we just found out that the present, too, is actively constructed? This again tends to deconstruct the idea of rigidly separated “past”, “future”, “present”. Perhaps it’s more like a bell curve with a sharply accentuated awareness in the middle, which we call “present”, with a relatively high imposition of sense data on the reconstruction, trailing off to a dimly aware past and even more dimly aware future, where sense data is far less vivid, and reconstruction and imagination play a far greater role.
6. Consciousness depends on manipulating time. Many cognitive abilities are important for consciousness, and we don’t yet have a complete picture. But it’s clear that the ability to manipulate time and possibility is a crucial feature. In contrast to aquatic life, land-based animals, whose vision-based sensory field extends for hundreds of meters, have time to contemplate a variety of actions and pick the best one. The origin of grammar allowed us to talk about such hypothetical futures with each other. Consciousness wouldn’t be possible without the ability to imagine other times.
Very much true – pointed out 2500 years ago by the Buddha in the Mahanidana Sutta: “It is to this extent that there is birth, aging, and death, passing away and reappearing; it is to this extent that there is a means of designation, language, and description, to this extent there is the range of wisdom, to this extent that the round (of samsara) turns such that this state of existence may be discerned, that is to say, with name-and-form together with consciousness.” The role of grammar, as pointed out above, is emphasized by the Buddha in such suttas as Samyutta 22.62. The basic idea is that consciousness is actively constructed by the linguistic, conceptualizing properties of the mind (nāma). Making sense of the stream of change in experience (birth, aging, death, and so on) requires the use of grammar, dividing the world up into past, present and future, from which we derive our abstract concept of “time”. There is, therefore, an intimate link between the designation “past” and the experienced reality “past”. In other words, it is our ability to name things that draws our attention to the past, and thereby keeps us trapped in it. I remember “yesterday”, and ruminate about what “was”, and what I can do about that “tomorrow”, and as long as I remain in the realm of “consciousness”, I cannot fully escape this construct.
7. Disorder increases as time passes. At the heart of every difference between the past and future — memory, aging, causality, free will — is the fact that the universe is evolving from order to disorder. Entropy is increasing, as we physicists say. There are more ways to be disorderly (high entropy) than orderly (low entropy), so the increase of entropy seems natural. But to explain the lower entropy of past times we need to go all the way back to the Big Bang. We still haven’t answered the hard questions: why was entropy low near the Big Bang, and how does increasing entropy account for memory and causality and all the rest?
Okay, entropy increases, I get that. But how does that relate to the big(ger) picture of Buddhist cosmology? In future universes, does entropy get a reboot? The notion of entropy in a very general sense fits in with impermanence, but I am not sure if there are any more specific Buddhist ideas that connect with this. One thinks of the notion that we are in a period of decline; but entropic disorder is not social decline, and anyway, with this (still entropically increasing) universe there is supposed to be a future upopia under Maitreya. Any thoughts?
8. Complexity comes and goes. Other than creationists, most people have no trouble appreciating the difference between “orderly” (low entropy) and “complex.” Entropy increases, but complexity is ephemeral; it increases and decreases in complex ways, unsurprisingly enough. Part of the “job” of complex structures is to increase entropy, e.g. in the origin of life. But we’re far from having a complete understanding of this crucial phenomenon.
This agrees with general Buddhist notions, that there is increase and decline of complexity, whether considered in the environment, society, or an individual’s mind, according to complex interweavings of conditions. The Buddha didn’t discuss complexity as such, although he did warn against the extremes of viewing the world as irreducibly complex or simple (sabbam nānattam, sabbam ekattam). Even though it is commonly assumed today that Buddhism is all about simplicity, this idea is not found in early Buddhism (except in the sense of a simple lifestyle, of course). Buddhist ideas and philosophy have, in fact, always been complex, and this stems right back to the Suttas. I think the Buddha, in accordance with the avoidance of extremes, used complex or simple teachings as appropriate to the subject and people at hand. That is to say, simplicity and complexity are in and of themselves value free, it is just that they need to be deployed appropriately. Since the world itself displays complexity, it is sometimes appropriate to use complex language to describe it. Insisting on simplicity as an absolute value impoverishes the ways we can describe the world, and hence impoverishes the ways we can respond to it.
9. Aging can be reversed. We all grow old, part of the general trend toward growing disorder. But it’s only the universe as a whole that must increase in entropy, not every individual piece of it. (Otherwise it would be impossible to build a refrigerator.) Reversing the arrow of time for living organisms is a technological challenge, not a physical impossibility. And we’re making progress on a few fronts: stem cells, yeast, and even (with caveats) mice and human muscle tissue. As one biologist told me: “You and I won’t live forever. But as for our grandkids, I’m not placing any bets.”
I’ll believe it when I see it. Until then, I agree with the comment by Steffen in the original article: “I am glad that death exists, and when my time arrives, I will go, to make place for the young generation. They deserve their chance.”
10. A lifespan is a billion heartbeats. Complex organisms die. Sad though it is in individual cases, it’s a necessary part of the bigger picture; life pushes out the old to make way for the new. Remarkably, there exist simple scaling laws relating animal metabolism to body mass. Larger animals live longer; but they also metabolize slower, as manifested in slower heart rates. These effects cancel out, so that animals from shrews to blue whales have lifespans with just about equal number of heartbeats — about one and a half billion, if you simply must be precise. In that very real sense, all animal species experience “the same amount of time.” At least, until we master #9 and become immortal.
This is one of those little factettes that doesn’t really affect anything, but is remarkable enough in its own way. Meditate and your heart will slow down, and you’ll live longer. The yogic idea correlates lifespan with the number of breaths we take – I don’t know if there is any empirical evidence for this, but it seems sensible enough. On a philosophical level, however, this reminds us that all our measures of time, whether lifespan, heartbeats, day and night, seconds, or cycles of a pulsar, or oscillations of electromagnetic radiation, are ultimately rooted in the human experience of time, all organic, messy, and subjective. No matter how confident the physicists become in their confident pronunciations of what time “really” is, don’t let your own experience be hijacked by the High Priests of Knowledge. What you experience is what time is for you, and that is the most important thing there is.