Thursday, May 14, 2020

why i am not a biopsychist

my last blogpost was really meant to be just for fun. but i do mean it for some of the ideas defended, specifically that there are only qualia as relationally understood, wrt to other experiences a person can have. this is to say, there are really no qualia as intrinsic properties. essentially, this means i’ll take something close to what is called a Frege-Schlick view, but will extend and defend it to make it less restrictive. so under some circumstances we can compare experiences across people after all, with the caveat that we can never be completely certain about such comparisons. this will allow us to resist a whole array of challenges to functionalism, e.g. inverted spectrum, zombies, etc. expect a more serious post / draft-y paper in about a month….


meanwhile, let’s talk about a different issue, re: how an important debate within the field is taking shape. it was one of those rare moments that something useful philosophically has come out of twitter of all places…

in a tweet i pointed out that panpsychism isn’t really taken seriously by scientists, as some may get that illusion by reading online stuff these days. Victor Lamme challenged me to do a poll. that led to some discussions. turns out, Victor isn’t a panpsychist. surprise, surprise. and in fact, i’m not sure who really is, within the scientific community…. apart from a few *really* far out folks.

but Victor isn’t a functionalist like i am either. by functionalist i don’t restrict myself to specific versions of it; i definitely do NOT think consciousness supervenes on ‘long-arm’ functional properties only. basically, i include for consciousness anything that can be done using software / algorithms. so any computational, representational properties may be relevant. i just don’t think the specific substrate for implementing the software is ultimately that crucial / irreplaceable.

so Victor decided to call himself a biopsychist, i.e. he believes that for a creature to be conscious, the relevant substrate needs to be biological. in fact, he thinks that most if not all living organisms are conscious!

i thought it’s a new name, biopsychism. but very quickly i stood corrected. as Evan Thompson pointed out, the term at least traces back to Ernst Haeckl in 1892.

i really like this way of setting up the debate: biopsychism vs functionalism (broadly construed, as i described above). this really gets at the heart of the issue, a sensible divide within the field, with very legit people on both sides. none of that far out / strawman stuff.

happily Ned Block seems to approve of the term. of coz he’s a biopsychist *of some sort*. he has long argued against functionalism and representationalism. something about the substrate is what really enables conscious experiences. does he think all biological organisms are conscious? probably not. so we should distinguish between some different versions of biopsychism. below i’ll do so, and also highlights some problems i see, even with rather weak versions of biopychism. despite these misgivings, unlike my stance on panpsychism as a scientist, i think biopsychism a position worth taking seriously.


the way Evan Thompson defines it, biopsychism states that all and only all living organisms are conscious. that is pretty strong. we can call this strong biopsychism or something. i think it’s quite unlikely to be true. (Evan gave a paper at PSA a couple of years ago, you can email him to ask for a copy; Peter Godfrey-Smith has also written on something related here)

the reason is, i think it’s pretty clear that even simple perceptual experiences involve fairly complicated computational processes that may critically depend on areas of the brain that are matured late in development and evolution, e.g. areas in the prefrontal cortex. a very simple living organism is not gonna have that.

but my take on the empirical matter aside, there is also a pretty damning conceptual problem. so let’s say you’re seeing two different images, a cat and a monkey, in binocular rivalry. when you are consciously seeing a cat, your cat-representing neurons fire. your monkey-representing neurons fire relatively little, as you are not conscious of the image of the monkey. but now, aren’t these monkey-representing neurons biological and alive?

this is related to what is called the 'combination problem', which is something that panpsychists also have to deal with. ultimately, a strong biopsychist will have to say something like, ok, so when you are not consciously seeing the monkey image, the monkey-representing neurons are not signaling consciousness for you. but they are themselves conscious. you just don’t feel their consciousness even though they are in your head.

this leads a rather hilarious way to make Ian Philips happy, i guess: there really is no unconscious perception, as Ian has argued. unconscious perceptual processes are conscious after all, but only becoz everything in the brain is conscious, with or without you~ this is a scenario rather different from the one Ian has argued for, of coz. he’s a reasonable guy. this, on the other hand, seems….. rather weird.


so some may hold a weaker version of biopsychism, and say, not all biological organisms are conscious. but if a creature is conscious, it must be biological. the relevant substrate can’t be replaced by something non-biological and yet functionally similar. if you replace it, the subjective experience will be gone, even if the subject behaves somewhat similarly. Ned is likely a biopsychist of this sort.

i am not sure about even this weaker version. because in biology, we look for mechanisms. not magical substrates. let’s say people found that consciousness requires a certain pattern of activity, involving some particular type of neuron, with certain transmitter receptors. then the scientific question to ask is what does it *do*. to the extent we figure out what does it do, why can’t we write down the computational algorithm that would mimic exactly what it does? then we should be able to replace it with something exactly functionally equivalent. if it does the same thing, exactly, and yet consciousness is missing... this just sounds like magic. and how are you ever gonna know?

but Bryce Heubner and Evan convinced me that there may be something to it. the idea is, yeah sure you can try to artificially mimic a biological mechanism. but the mechanism may be so inherently biological, that it involves implementing it in the right bio-habitat, letting it ‘survive’ on its own, do its metabolic work, etc. in that sense, yes, you may try to mimic it, but by the time you succeed…. maybe it isn’t so crazy to say that the artificial replacement is basically just as alive and biological.

i’m still not totally sure, but it’s true that in the old days, we talked about multiple realizability as if it is commonplace. given the same function, we can implement it any way we want. but increasingly, i think people do recognize that multiple realizability is not as common as we thought. often a mechanism can really only be implemented exactly and most efficiently in just one way.


so i’m still not sold, but i think it would make an interesting debate. and this may help the field move away from all those distractions we’ve seen in recent years too!

thinking ahead…. i imagine what kind of biopsychic i would become, if i were to eventually come round to it. i suspect the requirement for higher ‘cognitive‘ functions, e.g. those in the prefrontal cortex, is unlikely to give. if this turns out to be empirically wrong, that’s that. but i’m fairly sure for now. if anything, i may come to accept that: if we are to implement those higher functions as the way they work exactly, in conscious creatures like ourselves, yeah, maybe you’d end up having to do something kinda biological. perhaps we can call a person holding such a position a high functioning biopsychist. i’m not one yet, but i got the feeling that my good friend and co-author Richard Brown may be one!


  1. I'm so happy about this and the last post pushing the conversation in the right direction.

    A point that I think is under-appreciated, along the lines of what Bryce and Evan note: Hypothetically 'functionally equivalent' replacement parts/sub-systems/systems (e.g., advanced electronic components progressively replacing neurons a la Chalmers etc.) will not have the same *low level" reliability and random noise characteristics as their biological predecessors (bc they are fundamentally subject to their own). You could just push the problem further down but then I suspect you'd really be cornered into the replacement parts essentially being biological (possibly due to fundamental noise properties at the quantum level).

    Obvious following question is: Are reliability and randomness characteristics essential (in the relevant sense) to producing the phenomena? Not my field but I suspect so to some extent, and this might be able to be cashed out empirically / quantum theoretically (I'm not claiming that QM is magically responsible for consc — I'm conjecturing something much weaker and more specific).


    Looking forward to the draft-y paper!


    1. Sorry for the now huge comment but an obvious response is: "Neurons themselves naturally die / change their reliability characteristics over time. Progressively replacing parts with electronics changes you similarly in this respect".

      This gets to my overall view: Either way you're an evolving system with experiences/sensations/qualia that never recur exactly (just *different* interactions externally and internally) but we classify them as recurring in order to make sense of the world and ourselves. Same goes for 'consciousness' — it's not one thing; it's various aspects of the complex embedding of the evolving system in environment. So interesting systems like us don't have to be biological, but some changes are bigger than others (this can get empirical traction).

      The above plus self-models, causal/ID stories over time, and kinda random indexicality dissolve these kinds of philosophical 'consciousness' problems, I think.


  2. I believe Aristotle in the De Anima (On the Soul) held a similar position, when he claimed that "The soul is the first actuality of a natural body that has life potentially".

  3. Why do you place such emphasis on (visual) perceptual experiences when considering the prospect of strong bio-psychism? I have not read Godfrey-Smith in a while but, from memory, he raises the possibility of so-called 'primordial emotions' – roughly, feelings which reflect important changes in an organism's homeostasis like hunger, thirst, pain and so on. These feelings don't seem to have much to do with visual perception, and are perhaps unlikely to depend on primate visual specialisations.