Tag Archives: stream of consciousness

Time travel consciousness

Posted on by
9

In What’s Next? Time Travel and Phenomenal Continuity Giuliano Torrengo and Valerio Buonomo argue that our personal identity is about continuity of phenomenal experience, not such psychological matters as memory (championed by John Locke). They refer to this phenomenal continuity as the ‘stream of consciousness’. I’m not sure that William James, who I believe originated the phrase, would have seen the stream of consciousness as being distinct from the series of psychological states in our minds, but it is a handy label.

To support their case, Torrengo and Buonomo have a couple of thought experiments. The first one involves a couple of imaginary machines. One machine transfers the ‘stream of consciousness’ from one person to another while leaving the psychology (memories, beliefs, intentions) behind, the other does the reverse, moving psychology but not phenomenology. Torrengo and Buonomo argue that having your opinions, beliefs and intentions changed, while the stream of consciousness remained intact would be akin to a thorough brainwashing. Your politics might suddenly change, but you would still be the same person. Contrariwise, if your continuity of experience moved over to a different body, it would feel as if you had gone with it.

That is plausible enough, but there are undoubtedly people would refuse to accept it because they would deny that this separation of phenom and psych is possible, or crucially, even conceivable. This might be because they think the two are essentially identical, or because they think phenomenal experience arises directly out of psychology. Some would probably deny that phenomenal experience in this sense even exists.

There is a bit of scope for clarification about what variety of phenomenal experience Torrengo and Buonomo have in mind. At one point they speak of it as including thought, which sounds sort of psychological to me. By invoking machines, their thought experiment shows that their stream of consciousness is technologically tractable, not the kind of slippery qualic experience which lies outside the realm of physics.

Still, thought experiments don’t claim to be proofs; they appeal to intuition and introspection, and with some residual reservations, Torrengo and Buonomo seem to have one that works on that level. They consider three objections. The first complains that we don’t know how rich the stream of consciousness must be in order to be the bearer of identity. Perhaps if it becomes attentuated too much it will cease to work? This business of a minimum richness seems to emerge out of the blue and in fact Torrengo and Buonomo dismiss it as a point which affects all ‘mentalist’ theories. The second objection is a clever one; it says we can only identify a stream of consciousness in relation to a person in the first place, so using it as a criterion of personal identity begs the question. Torrengo and Buonomo essentially deny that there needs to be an experiencing subject over and above the stream of consciousness. The third challenge arises from gaps; if identity depends on continuity, then what happens when we fall asleep and experience ceases? Do we acquire a new identity? Here it seems Torrengo and Buonomo fall back on a defence used by others; that strictly speaking it is the continuity of capacity for a given stream of consciousness that matters. I think a determined opponent might press further attacks on that.

Perhaps, though, the more challenging and interesting thought experiment is the second, involving time travel. Torrengo is the founder of the Centre for Philosophy of Time in Milan, and has a substantial body of work on the the experience of time and related matters, so this is his home turf in a sense. The thought experiment is quite simple; Lally invents a time machine and uses it to spend a day in sixties London. There are two ways of ordering her experience. One is the way she would see it; her earlier life, the time trip, her later life. The other is according to ‘objective’ time; she appears in old London Town and then vanishes; much later lives her early life, then is absent for a short while and finally lives her later life. These can’t both be right, suggest Torrengo and Buonomo, and so it must surely be that her experience goes off on the former course while her psychology goes the other way.

This doesn’t make much sense to me, so perhaps I have misunderstood. Certainly there are two time lines, but Lally surely follows one and remains whole? It isn’t the case that when she is in sixties London she lacks intentions or beliefs, having somehow left those behind. Torrengo and Buonomo almost seem to think that is the case; they say it is possible to imagine her in sixties London not remembering who she is. Who knows, perhaps time machines do work like that, but if so we’re running into one of the weaknesses of thought experiments methodologically; if you assume something impossible like time travel to begin with, it’s hard to have strong intuitions about what follows.

At the end of the day I’m left with a sceptical feeling not about Torrengo and Buonomo‘s ideas in particular but about the whole enterprise of trying to reduce or analyse the concept of personal identity. It is, after all, a particular case of identity and wouldn’t identity be a good candidate for being one of those ‘primitive’ ideas that we just have to start with? I don’t know; or perhaps I should just say there is a person who doesn’t know, whose identity I leave unprobed.

Consciousness – a stream?

Posted on by
11

flowAn interesting piece from Evan Thompson on the ‘stream of consciousness’. The phrase is probably best known now as the name for a style of modern literary prose, but it originates with William James. Thompson compares James’ concept of a smoothly rolling stream with the view taken by the Buddhist Abidharma tradition, which holds that closer consideration shows the stream to consist of discrete parts.
Thompson quotes two pieces of experimental evidence which broadly suggest the Abidharma view is closer to the truth. Experiments conducted by Francisco Varela on the young Thompson himself suggested that perception varied in harmony with the brain’s alpha waves, although it seems the results have not been successfully replicated since. The other study related to the ‘attentional blink’ in which a stimulus rapidly following another is likely to be missed. It seems successful attempts by the subjects were accompanied by a kind of phase locking with theta rhythms; certain meditative techniques of mindfulness improved both the theta phase locking and the ability to perceive the following stimulus.
Overall, Thompson concludes that conscious perception isn’t smoothly regular, but comes in pulses. Perhaps we could say that it’s more like the flow of a bloodstream than that of a river.
Still, though – is consciousness actually continuous? Suppose in fact that it was composed of a series of static moments, like the succeeding frames of a film. In a film the frames follow quickly, but we can imagine longer intervals if we like. However long the gaps, the story told by the film is unaffected and retains all its coherence; the discontinuity can only be seen by an observer outside the film. In the case of consciousness our experience actually is the succession of moments, so if consciousness were discontinuous we should never be aware of it directly. If we noticed anything at all, it would seem to us to be discontinuity in the external world.
It’s not, of course, as simple as that; there are two particular issues. One is that consciousness is not automatically self-consciousness. To draw conclusions about our conscious state requires a second conscious state which is about the first one. We’ve remarked here before on Comte’s objection that the second state necessarily disrupts the first, making reliable introspection impossible: James’ view was that the second state had to be later, so that introspection was always retrospection.
This obviously raises many potential complications; all I want to do is pick out one possibility: that when we introspect the first and second order states alternate. Perhaps what we do is a moment of first-order thinking, then a moment of second order reflection on the moment just past, then another moment of simple first-order thought and so on; a process a bit like an artist flicking his gaze back and forth between subject and canvas.
If that’s what happens, then it would clearly introduce a kind of pulse into our thoughts. This raises the curious possibility that our normal thoughts run smoothly, but start to pulsate exactly when we start to think about them. The pulse would be an artefact of our own introspection.
The other issue is more fundamental. Both James and the Abidharma school apparently assume that our thoughts seem to come in a continuous flow. Well, mine don’t. Yes, at times there is a coherent narrative sequence or a flowing perceptual experience, but these often seem like achievements of my concentration rather than the natural state of my mind. At least as often, things pop up unbidden, stop and start, and generally behave less like a flow and more like one damn thing after another. It’s noteworthy that the stream of consciousness in literature is not characterised by smooth logical development, but by a succession of fragmentary ideas and perceptions, a more realistic picture in many ways.
However, reflecting on a train of thought afterwards we can sometimes see links that we didn’t notice before. Several of our thoughts which seemed unrelated all bear on a particular anxiety or concern, say; scarcely a novel phenomenon in either psychology or literature. Hypothetically we might guess that our conscious moments are indeed part of a coherent stream, but one which includes important unconscious or subconscious elements, If we could see the whole process it might make fine logical sense, but all we get are the points where the undulating serpent’s back breaks the surface.
Neither of those issues disturbs Thompson’s modest conclusion that there is a kind of pulse on the surface of the stream; but there is deep water underneath, I think.