I've heard a few introductory lectures about Buddhism. One question that invariably comes up is something along the lines of "Uh, so, you guys believe in reincarnation, then?"
Buddhism has a reputation for being a rational religion—systematic, pragmatic, science-friendly, non-supernaturalistic, even intellectual. Perhaps for this reason, the concepts that appear, on the surface, to be supernaturalistic easily rise to the surface: karma and rebirth in particular.
Although I'm making some progress, I still don't quite get rebirth. However, over the past couple of years that I've done some serious thinking about Buddhism, I have been repeatedly struck by the way difficult and hard to digest concepts suddenly fall into place. Something that doesn't seem to make sense finds a context and clicks. It's there for a reason. Nowadays my default assumption about Buddhist stuff that doesn't appear to make sense is that I don't understand what it means, so I kick the can down the road a lot. I've been reading bits and pieces from Dōgen's Shōbōgenzō this way, for example—some bits are very easy to get to grips with; other bits don't make any sense at all, but might suddenly do so later.
Thanks to a bunch of stuff I've read on and off the Net, and especially to a few people kind enough to answer some of my questions,1 the fog has started to clear a bit, even if I still have some unresolved questions.
There are a whole bunch of different views, or metaphors, for rebirth that I've come across.
The naive viewLike most people, I started out with a naive view of rebirth. I assumed it meant simply a belief that when you die, your 'soul'—or some close equivalent—leaves your body and is reborn as something else, with the specifics being determined by your 'karma,' which I assumed meant a collection of merit points and demerit points, adding up to some kind of net positive or net negative. So if you did your best to live as a decent human being, you might be reborn as a monk; if you went around being a dick, you'd be reborn as a cockroach, and if you do a really good job of meditation, you might escape the whole thing into some blissful state called 'nirvana.' This always seemed a bit silly, much like any religious fairy-tale made up to make death a bit more palatable.2
Relatively quickly, I discovered that this isn't quite how Buddhists see things, although some flavors of Buddhists do come quite close to it. This leads to:
The Appropriating Consciousness viewWhen studying Vasubandhu, one of the founders of Yogācāra Buddhism, I came across another description and explanation of rebirth. This could be called the Appropriating Consciousness view. It's a great deal more refined and interesting than the naive view, and even if you don't quite swallow all of its implications, it's well worth studying.
In Vasubandhu's model, the personality consists of a bundle of interleaved streams of consciousness-moments called cittas. There's a large variety of different types of cittas, such as perceptions of sense-impressions, motivational dispositions, volitional actions, ideas of 'objects' and 'subjects' and so on and so forth. Each citta conditions the citta that immediately follows it. So, for example, a perception of pain could condition a motivational disposition to avoid the pain, which could condition a volitional action intended to stop the pain.
The interesting thing about volitional actions in Vasubandhu's model is that they also condition a specific type of citta, which he calls a "seed." This seed-citta is different from other cittas in that it cannot be directly apprehended; it stays somewhere in what Freud would have dubbed the 'subconscious.' However, in other ways seed-cittas behave just like other cittas: they only last an instant, and their only effect is to condition other cittas. Most of the time, seed-cittas condition other seed-cittas, still in the 'subconscious.' It is only when a seed-citta conditions a citta within the conscious part of the mind that you can become (indirectly) aware of their existence. For example, a memory might surface, or an aversion or attraction might arise due to something that happened a long time ago. One highly significant feature of this model is that memories and other 'latent' things in the mind aren't static and persistent; they're dynamic series of consciousness-moments, each similar but not identical to the preceding one. Thus we forget, have distorted memories, develop and alter habits, and so on.
Vasubandhu called the interleaved bundle of streams of seed-cittas the seed-consciousness, root-consciousness, or appropriating consciousness. He also made it very clear that this root-consciousness is nothing more than the collection of streams of seed-cittas, no different from other streams of cittas in any way other than by way of happening somewhere it's not possible to reach them with the conscious mind. No special substratum or substance is needed for them any more than for the cittas happening at the conscious level.
I really like this model. It describes what goes on in the mind in a very precise and useful way, accounting for all kinds of things like memories, forgetfulness, conditioned reactions, and so on and so forth. What's more, it very neatly accounts for karma. An unbeneficial action—one motivated by ill-will, greed, delusion, etc.—would deposit a seed-citta that would eventually mature into something nasty, whereas a beneficial action would do the opposite. It's also a highly parsimonious solution, because it only posits a few simple concepts that can be categorized into a manageable number of classes, and makes no major metaphysical assumptions.
Now, Vasubandhu also labeled this collection of seed-citta-streams the appropriating consciousness. This is because of his take on rebirth. He believed that when you die, this collection of seed-cittas will condition another birth, and the karmic process of seeds maturing and conditioning other seeds will continue in that life. So, it's not that this seed-consciousness is reborn as something; instead, it appropriates a suitable vessel to continue evolving. However, the seed-consciousness does not constitute a 'self' any more than any other stream of cittas, because that's all it is—a bundle of streams of consciousness-moments. His description of death is simply 'a special transformation in the consciousness-series' and 'a cessation not through contemplation,' no different in principle from forgetting something or falling asleep—also 'cessations not through contemplation'—or falling in love, becoming enlightened, or experiencing intense pain after hitting your thumb with a hammer—also 'special transformations in the consciousness-series.'
I understand the Tibetan Buddhist view of rebirth is somewhat similar to this; they're certainly pretty big on Vasubandhu. It's pretty easy to plug in the concept of 'bardo'—this would be the state of the seed-consciousness after the death of one body and before it has appropriated another.
I have some problems with this second part of Vasubandhu's model. I can see how cittas condition other cittas within an 'individual personality.' I can also see how cittas in one 'individual personality' condition cittas in another 'individual personality'—for example, if you walk into a room where someone is feeling surly, some of that surliness will rub off on you, even if the surly individual doesn't do anything particularly dramatic. However, I do not see how one particular bundle of seed-citta-streams could condition one particular rebirth. That would require positing a bunch of metaphysical unknowables again—namely, some mechanism by which the bundle could maintain its coherence through the death of the 'individual personality' hosting these streams.
The Thermodynamic ViewThe third model of rebirth that I've come across could be dubbed the Thermodynamic View. While I've had it explained to me in a number of different ways and metaphors, from billiard balls to sacks of rice passed from one person to another, Vasubandhu's model (minus the second part) will do just fine.
In this model, we have intentional actions conditioning consciousness-moments and karmic seeds just like per Vasubandhu. The change of perspective is that the process of conditioning itself is seen as being the same thing as rebirth. We're reborn every instant, as each flickering consciousness-moment conditions the next, similar but not identical to the previous one.
Moreover, we have intentional actions conditioning rebirths in other people, also constantly and at every instant. What I say or do affects you and conditions your rebirth in the instant after it registers with you. If I say something unkind to you, you might get hurt or angry; that will manifest in your actions, and spread the ripples of karma—intention, action, and consequence—ever further. Samsara is a system where this continuously created and maturing karma bounces around and changes form, just like energy in a closed system can neither be created nor destroyed, but only transformed.
This description is closest to my current take on the matter. Birth and death are still 'special transformations in the consciousness-series,' no less, no more. Rebirth is the continuous process of recreating the self moment to moment. Karma is the continuous process of intentional action conditioning this recreation of the self, in the one who acts and the ones who are affected by the consequences of the action (i.e., ultimately everybody and everything).
There is nothing supernatural involved, just a radical view of what a 'personality' is, and the interconnectedness of everything and everyone. Anattā, anicca, and dukkha, all dancing together in the intricate steps of pratītya-samutpāda to the music of karma, on the great dance floor of saṃsāra.
The Problem of Past LivesBuddhist literature contains a good deal of stuff about enlightened teachers recalling and describing their past lives. One of the siddhis—perfections—that intense meditational practice is said to produce is this ability. The Jātaka is a book in the Pāli Canon that contains stories presented as accounts of Siddhattha Gotama's past lives. Many Buddhists take these descriptions very seriously.
Vasubandhu's 'appropriating consciousness' model of rebirth can account for recollection of past lives: in it, death and appropriation of a new body are simply transformations in the consciousness-series, there is a transfer of karmic seeds from one life to another. There is nothing in principle to prevent a sufficiently accomplished yogin from attaining the ability to cause these seeds to resurface, and thereby recall 'his' past lives. From the point of view of textual orthodoxy, Vasubandhu's model is impeccable. Its main problem is related to information theory: we need some medium through which those coherent memories and karmic seeds are transferred from one life to another, which requires some metaphysical assumptions bordering on the supernatural, which I find difficult to swallow.
The 'thermodynamic model' doesn't have this problem. However, it can't explain 'past lives.' In it, actions, causes, and consequences bounce around samsara, but bundles of these chains are only temporarily coherent, and the death of an individual disrupts the coherence. Karma does keep on going on as actions condition rebirths. If I hurt your feelings today and immediately die, that won't stop the chain of causation started by my ill-willed action—my subsequent death could even aggravate the consequences, since we wouldn't have the opportunity to kiss and make up. However, it is not possible to say that 'that life' was a past life of 'this life,' except in the sense that, perhaps, every life was the past life of this life, and every life is also the future life of this life. Coherent structures such as memories and narratives don't stay together.
The only solutions to this problem that I can see are either to accept Vasubandhu's 'appropriating consciousness view' on faith with its metaphysical implications, or to reject a literal reading of those parts of the Buddhist canon that speak of recollections of past lives.
My Provisional ViewI'm still working my way around this question (and many others). Rebirth is quite interesting in that it connects up a good many of the most central features in Buddhist teaching—karma, no-self, impermanence, suffering, samsara, interdependence. A lot of Buddhist philosophy just stops making sense if you reject the notion of rebirth outright, in any of its forms.
However, I can't see how the notion of past lives would be similarly central to it. In fact, if we accept the notion of anattā—no-self—the whole notion of a specific past life becomes problematic. Whose past life are we talking about anyway, which one, and why that one and not some other one? What's more, if memories and karmic conditioning consist of streams of mind-moments constantly conditioning each other below our level of awareness, perfect recall would become impossible by definition even in what's normally thought of as a single life, never even mind such drastic transformations in the consciousness-series as 'death' and 'birth.'
I still can't say I understand what's meant by rebirth. What has become clear, though, is that there's a broad range of views on the topic within Buddhism. There doesn't appear to be a particularly strong conformity around this topic even within particular Buddhist traditions; for example, I've come across Theravadins and Zennies who appear to have a very literal view of rebirth including the accounts of past lives, and other Theravadins and Zennies who appear to hold the 'thermodynamic view' of it, or something quite close to it in any case. Tibetan Buddhists appear to identify most closely with something like the 'appropriating consciousness' view; I believe this must have something to do with their institution of reborn tulkus, which doesn't really make much sense if you're not able to determine which particular life follows from which other particular life and don't have some explanation for this process.
One thing I have learned is that this is something of a contentious topic, which sometimes excites some strong feelings. I'm unfortunately nowhere near familiar enough with the relevant sources yet to be able to decide for myself what those sources actually mean to say. Given the diversity of views among people who are familiar with these sources, though, I think it's safe to say that there isn't a pat answer to be had there.
As far as I'm concerned, that's a very good thing indeed.
2Les Thanatonautes by Bernard Werber is a pretty cool sort-of-sci-fi novel based on the conceit that this is how it works, and people find a way to explore the intermediate state between rebirths; this state is known as The Continent of the Dead. Well worth a read, if you read French—I don't think it's been translated to English.
Recommended readingBernard Werber: Les Thanatonautes