zombies

Zombies are hypothetical creatures which are functionally identical to us, but they lack qualia altogether. If they are possible, functionalism can’t be right. If such possibilities are conceivable, perhaps it means that functionalism is at least conceivably wrong.

There are a few senses in which zombies can be functionally identical to us. Suppose we merely mean they can refer to and act on the same objects in the world like we do. Then sure some robot-like creatures can interact with objects in the world without being conscious.

But if we mean that they are functionally fully identical to us, as in the whole mental algorithm is consistent with what we have, then we should recognize that they can’t be coherently conceived to be nonconscious. Such ‘zombies’ will know what it is like to have certain experiences. They can tell you scarlet is a bit like crimson, not much like pink or purple, etc, from a subjective point of view. This means, if you ask them if there is something it is like to see colors, they will truthfully say yes, for the same reasons we do. On the other hand, if you ask them what it is like to experience some subthreshold firing of neurons in the visual cortex, it should draw a blank. And this would not be merely because they don’t know enough about neuroscience. Even if you actually stimulate their visual cortices that way, they still wouldn’t know what you were talking about. In this sense, they are just like us.

Of course, the anti-functionalist can say that they only behave or talk as if they consciously see. But how else do you know if anyone is conscious, besides their expressing that they think so and your lack of reason to doubt that they are lying or deluded? 

Let’s say we have some Martians, who truthfully agree with us that there is something it is like to see red and other colors. And yet, when asked what it is like to smell, it draws a blank. If odors could nevertheless influence their behavior, we probably would think that they have olfactory processing. In that case, what else apart from consciousness can account for the difference between their vision and olfaction? According to them, in one modality, there is something it is like, and in the other, there isn’t. If they aren’t lying or crazy, what else is the difference?

This is to say, if a creature is capable of thinking meaningfully whether there is something it is like to have a certain experience, then whether the creature is inclined to truthfully think so is the truth of the matter. As such, zombies in a fully functional sense are simply not coherently conceivable. Either they truthfully think there is something it is like to have some experiences, in which case they aren’t zombies; or they do not think so, in which case they are not functionally like us at all.

[this literature is vast and mine will never be the last words, of coz. hence this is a blogpost not a paper. my goal is just to hopefully convince some of my scientist colleagues that some functionalist defense is possible, and it needn't be overly complicated.]

Cognitive Neuroscience of Consciousness Trainee Recruitment Conference

Hi everyone,

In a previous post I discussed the tricky business of finding a suitable lab for grad school in this field. After some discussion with lab members and colleagues we are now organizing the following event:

- What is it about? 

The Cognitive Neuroscience of Consciousness Trainee Recruitment Conference 2020 (link to registration here) will feature 12 PIs in the field. Most of them will have short videos uploaded in the coming few weeks, to showcase some current projects in their labs. There will then be 3 panel sessions where registered attendees can ask questions and discuss with the PIs about the presented projects, working in their labs, career advice, grad school applications, etc.

- When are the meetings? Who are the PIs?

They are tentatively scheduled as follows:

Aug 26 Wed 11am (PST) will feature Rachel Denison (Boston University), Tony Ro (City University of New York), Jason Samaha (UC Santa Cruz), & Emily Ward (U Wisconsin-Madison)

Sep 1 Tues 11am (PST) will feature Eve Isham (U Arizona), Brian Odegaard (U Florida), Giancarlo Vanini (U Michigan), Caroline Robertson (Dartmouth) 

-- Update: Profs Isham & Robertson will not be putting up videos; please check their websites for their research: 

http://cat.lab.arizona.edu/
https://pbs.dartmouth.edu/people/caroline-robertson

Sep 3 Thur 11am (PST) will feature Ruth Rosenholtz (MIT), Megan Peters (UC Irvine), Michael Cohen (Amherst), Phil Corlett (Yale)

-- Update: Prof Cohen won't be putting up a video; please check his research website @ http://www.michaelacohen.net/

We expect each meeting to last for about an hour.

- Where will the meetings take place?

These will be virtual meetings online. We plan to use Zoom.

- Who can attend?

The meetings are primarily for trainees, broadly defined to include prospective grad students, research assistants, and postdocs. But others are welcome too. All you need to do is to register here with a correct email address so as to receive further information for the Zoom meetings.

But please be reminded that the meetings will take a semi-synchronous format, that is we will not show the videos at the meeting. You should watch them prior to the meeting, during which we'll go straight to Q&A.

- Where do I find the videos?

Watch this space. Links to the videos / background materials will be added gradually in the coming weeks, as hyperlinks associated with the names of the PIs listed in the schedule above. For example, you can click on Ruth Rosenholtz's name for her video.

- Do I have to pay?

No, although you have to register to attend the meeting, it is free.

- Who are the organizers?

All the work has been done by Cody Cushing and Taylor Webb from my lab, together with our frequent collaborator Matthias Michel.

- Why are all the labs featured based in the US?

Sorry but this is the purpose and current scope of the meeting. The field faces unique challenges in US, due to various factors including funding structure and popular media misrepresentation. Perhaps in the future others will set up similar meetings for other regions too. For now, please forgive our limited logistical bandwidth.

- I have a question not covered above ....

The ideal place may be to ask me on twitter, so others can see the question and my response to it too.

Mary & Maru

In Jackson’s knowledge argument, Mary is a talented color scientist, who was prevented from seeing color since birth. Despite that deprivation, she has studied all there is to know about color processing. When she finally sees something red for the first time, will she learn something new? The argument goes that she probably will, and it means that there is something to having a conscious experience that outstrips representational knowledge, and perhaps also functionalism as a result. 

Empirically, we know that sensory deprivation of this kind can severely limit normal brain development. After years of such deprivation, chances are her ability to see color may be permanently gone, or drastically changed somehow. To assume that she can see red exactly like we do is to force our imagination through some plausibly incoherent assumptions.

So instead, why don’t we consider a more realistic example that would serve the same purpose: Maru is a young child who has never tasted natto before. Genetically, she is a supertaster. Like many young children in her culture, she can cook simple meals for herself. She is deeply interested in food and culinary art. But her own parents dislike natto, which is not so uncommon in her culture. So she has never tried it. She heard that it has such a distinctive flavor that either she will love it or hate it. She has been told that natto is basically a kind of fermented soybean. So it is in a way like miso, although the flavor driven by the fementedness is a lot more intense. It is not necessarily as salty, but it is even funkier than old cheese, or Chinese fermented bean curd. In fact, it is on the level of Taiwanese stinky tofu, although for natto the intensity is more on the palette than on the nose. It has a gooey texture, like it is mixed with raw egg white or something. It’s basically ineffable what it is like, she’s been told. She has to try it to find out herself.

The inquisitive and imaginative Maru-chan asks a lot of questions about this curious food. She regularly thinks about what it would taste like. One morning, after a slumber party at her best friend’s, they have natto and rice for breakfast. So she finally gets to try it for the first time. Does she learn anything new?

Obviously, that depends on how Maru-chan’s ‘research’ has gone. But one possibility is, she may say: this is exactly how I always imagined it to be! Based on the other experiences that are familiar to her, with some remarkable level of imagination, she might have actually figured out what it would taste like. On reflection, hasn’t that also happened to us sometimes, for other stimuli? Experiencing something for the first time doesn’t always feel so surprising. So it is possible that she will learn nothing fundamentally new. Tasting natto just confirms what she already knows without first-hand conscious experience. In that case, conscious experiences don’t necessarily outstrip representational knowledge.

Alternatively, it could be that Maru does learn something significantly new. Natto isn’t quite like what she’s imagined it to be. From here, perhaps she gains the ability to imagine it correctly. She also learns some new self-knowledge: this is what natto tastes like to her. At a subpersonal level, some mechanisms in her brain acquire the new information that this is what the relevant sensory vehicle is like, for natto - it is a bit like the vehicles for this other taste, that other taste, nothing like the vehicles for the tastes of ikura, karaage, etc. This is not the sort of stuff one can learn by reading books. Even if one learns the information as a person, it doesn't mean the relevant mechanisms in the brain will get it too.

So in either case there’s no challenge to functionalism. 

P.S.  This story is inspired by my experience of once dining with an ardent anti-functionalist in a Japanese restaurant in downtown Manhattan. I tried to convince the adventurous philosopher not to order the natto dish, but I failed.