Can they suffer?

Jared Moore and David Gottlieb

How things seem

Vitalism, Cartesian

A figure from Descartes’ book showing the role of the pineal gland

A figure showing the relationship between dualism and Monism

Homunculi

A homunculus in a sperm cell

Things are not what they appear to be

http://www.lifesci.sussex.ac.uk/home/Chris_Darwin/SWS/

Things are not what they appear to be

Our conscious experience does not arrive raw from nature.

http://www.lifesci.sussex.ac.uk/home/Chris_Darwin/SWS/

Consciousness is not what it appears to be

Objects experienced are represented within the mind of the observer

Presenting the Cartesian Theater staring: You!

(Consciousness is an “illusion.”)

Zombies and the “Hard Problem”

Why should physical processing give rise to a rich inner life at all? It seems objectively unreasonable that it should, and yet it does (David J. Chalmers 1995a, 2)

A drawing of a philosophical zombie

Blackmore and Troscianko (2018)

Theories of Consciousness

A diagram showing the attention schema theory of consciousness.

Awareness as a computed feature. A green apple is encoded in the visual system as a set of stimulus features described by chunks of information that are bound together. The property of awareness might be another computed stimulus feature bound to the rest.

Awareness is a description of attention (Graziano 2013)

[I] [am aware of] [X].

Graziano (2013)

multiple realizability of attention?

Attention mechanisms in artificial neural networks: The colors in the attention indicate that these weights are constantly changing while in convolution and fully connected layers they are slowly changing by gradient descent.

Functionalism

as flight

A brown pelican flying

A plane flying

Is it a difference that makes a difference (Bateson)?

The “computation” (or function) of flight

L = ∮pn ⋅ k dS

where

S is the projected (planform) area of the airfoil, measured normal to the mean airflow;
n is the normal unit vector pointing into the wing;
k is the vertical unit vector, normal to the freestream direction.

https://en.wikipedia.org/wiki/Lift_(force)

The air moving faster on the top of a foil

Human minds have a particular biochemical basis, but this is a contingent feature, not a necessary one. A physical system has mental states in virtue of its abstract causal organization, that is, in virtue of how its states are connected to sensory input, behavioral output, and each other. In us, the causal roles characteristic of the mental have particular physical realizers, and those physical realizers are brain states with a chemistry of proteins, lipids, nucleic acids, and so on. But other realizers could, in principle, play the same roles. This means that a computer with a very different chemistry could have physical states that realize the causal roles characteristic of a human mental life, if suitably programmed and (perhaps) if connected to a robot of the right kind. […] Further, any system that has the same functional and hence cognitive profile as a human agent must have the same subjective experiences (Godfrey-Smith 2016)

What does this mean? Explain to your neighbor

The Neural Doctrine

nervous systems and probably parts of nervous systems are themselves naturally evolved computers—organically constituted, analog in representation, and parallel in their processing architecture. They represent features and relations in the world and they enable an animal to adapt to its circumstances. (Churchland and Sejnowski 2016)

Neural Replacement

[A neuron is replaced with] a silicon chip that performs precisely the same local function as the neuron. We can imagine that it is equipped with tiny transducers that take in electrical signals and chemical ions and transforms these into a digital signal upon which the chip computes, with the result converted into the appropriate electrical and chemical outputs. As long as the chip has the right input/output function, the replacement will make no difference to the functional organization of the system. (David J. Chalmers 1995b)

What do you think?

Why replacing a neuron is hard

Spatiotemporal characteristics of a neuron’s spiking responses.
- e.g., very fast, small, and long extensions
Transducers and chemical signaling
- e.g., many kinds of input; “tens of thousands of selective ion channels”; nitrous oxide spreads everywhere
Biophysical sensitivities
- e.g., temperature dependence, anything could be used
Self-modification and other non-spiking effects
- e.g., plasticity, growing new connections
The functional role of glia and other non-neuronal cells
- If all neurons do is influence each other, why not include astrocytes?

Cao (2022)

Differences that makes a difference?

This is your AI on drugs

An egg in a frying pan with the caption “this is your brain on drugs”

What functions of the brain are necessary?

I’m going to the moon, and I am going to take…

I’m going to remake the brain (or consciousness), and I am going to implement…

e.g., silicon based neurons, nitrous oxide, parallelization, blood vessels, glial cells, etc.

Replace large parts of the brain? The whole body?

Fear? Adrenaline from the adrenal glands on the kidneys?
Drugs through blood vessels

Even if it were possible for such a [full scale silcon realization of the brain and body] to realize the same behaviors, it would not be due to its identical functional organization. Rather, it will be because differences in its functional organization accommodate the differences in its material constitution, with mutual compensation allowing the system to approximate the original behavior. (Cao 2022)

What do we think Cao means by this?

Sentience

Subjective experience

Godfrey Smith is using biology as his guide to map the boundary conditions of subjective experience.

How does he differentiate sentience or subjective experinece from consciousness?

I will use the phrase “subjective experience” for the broadest category of phenomena here, also describable by saying that some states of some systems feel like something to the system itself, and others do not. (Godfrey-Smith 2016)

What’s life got to do with it?

What are the two poles Godfrey-Smith identifies?

Metabolism and Agency

Godfrey-Smith explores whether agency and sentience are biologically (and metaphysically) tethered.

Maybe they aren’t…

[Agency] is a good idea for any (metabolically) living thing, and hence it readily evolves, even though it has no necessary connection to the metabolic side of life. (Godfrey-Smith 2016)

But maybe they are…

Do you get to count as doing the things living systems do (namely, be sentient) if you’re not trying to stay alive (maintain your equilibrium)?

[W]e must confess that perception, and what depends upon it, is inexplicable in terms of mechanical reasons, that is through shapes, size, and motions. If we imagine a machine whose structure makes it think, sense, and have perceptions, we could conceive it enlarged, keeping the same proportions, so that we could enter into it, as one enters a mill. Assuming that, when inspecting its interior, we will find only parts that push one another, and we will never find anything to explain a perception. (Leibniz)

Could life have arisen at a human scale instead of at a microscopic scale?

theoretical (metaphysical) possibility: Is it conceivable? is it logically plausible in some possible world?
nomological (nomos, law-like) possibility: “physically-possible-in-this-world-if-we-had-enough-resources” (Cao 2022)

A diagram of Maxwell’s demon

Conceivability

Arguments against materialism based on conceivability rely on the trustworthiness of intuitions about what the particular physical processes inside us can produce. Once we see what those physical processes are actually like, the trustworthiness of the crucial intuitions is much reduced (Godfrey-Smith 2016)

What would Godfrey-Smith say about neural replacement?

My claim is not that non-biological materials that do all the same things might not count because of their physical nature. Rather, the usual candidates offered as a non-biological basis for mentality will not do the same things. (Godfrey-Smith 2016)

Functions impose constraints on their realizers. Complex integrated functions impose more constraints than ones that can be decomposed into simpler independent functions. Mental functions are both complex and thickly integrated with physiological functions. So the functional organization of the brain at the cellular level exhibits characteristics that make it unlikely to be multiply realizable at that level of description. (Cao 2022)

That means that as our best scientific account of neural function improves, proponents of [multiple realizability] should update their bets accordingly. I would add that since these are empirical claims, the burden of proof should lie at least as heavily on proponents of [multiple realizability] as on its opponents. (Cao 2022)

functions, all the way down

while a mousetrap has plenty of “unemployed” properties to spare after its behavior and functional organization have been accounted for—properties that could be different in an alternate realization without affecting the function—the brain does not. (Cao 2022)

$A circular fractal by M. C. Escher$

flight, but you’ve got to metabolize

A brown pelican flying

A bird-plane flying

So what?

Sentience isn’t what matters, consciousness is.

Johansson et al. (2005)

Fig. 1. A snapshot sequence of the choice procedure during a manipulation trial. (A) Participants are shown two pictures of female faces and asked to choose which one they find most attractive. Unknown to the participants, a second card depicting the opposite face is concealed behind the visible alternatives. (B) Participants indicate their choice by pointing at the face they prefer the most. (C)The experimenter flips down the pictures and slides the hidden picture over to the participants, covering the previously shown picturewiththesleeveofhis moving arm. (D) Participants pick up the picture and are immediately asked to explain why they chose the way they did.

There was a very low level of concurrent detection. With a total of 354 M trials performed, only 46 (13%) were detected concurrently. Not even when participants were given free deliberation time and a set of LS faces to judge were more than 27% of all trials detected this way.

“Our access to our own thinking, and especially to the causation and dynamics of its subpersonal parts, is really no better than our access to our digestive processes; we have to rely on the rather narrow and heavily edited channel that responds to our incessant curiosity with user-friendly deliverances, only one step closer to the real me than the access to the real me that is enjoyed by my family and friends” (Dennett 2017, 12)

So shouldn’t we just be able to throw out all of the lower level dynamics anyway?

Blackmore and Troscianko (2018)

Exit ticket

Close your eyes

Take some time to simply notice what you are conscious of. If you find yourself thinking of something else, that’s fine, just notice that and continue the exercise. If anything feels either good or bad, notice that as well. On your exit ticket, describe what you were conscious of.

References

Blackmore, Susan J., and Emily Troscianko. 2018. Consciousness. 3rd edition. Abingdon, Oxon ; New York, NY: Routledge. https://orbiscascade-washington.primo.exlibrisgroup.com/view/action/uresolver.do?operation=resolveService&package_service_id=89860776100001452&institutionId=1452&customerId=1450&VE=true.

Cao, Rosa. 2022. “Multiple Realizability and the Spirit of Functionalism.” Synthese 200 (6): 506. https://doi.org/10.1007/s11229-022-03524-1.

Chalmers, David J. 1995a. “Facing up to the Problem of Consciousness.” Journal of Consciousness Studies, 20.

Chalmers, David J. 1995b. “Absent Qualia, Fading Qualia, Dancing Qualia.” In Conscious Experience, edited by Thomas Metzinger, 309–28. Ferdinand Schoningh.

Churchland, Patricia S., and Terrence J. Sejnowski. 2016. The Computational Brain. The MIT Press. https://direct.mit.edu/books/book/3556/the-computational-brain.

Dennett, D. C. 2017. From Bacteria to Bach and Back: The Evolution of Minds. First edition. New York: W.W. Norton & Company.

Godfrey-Smith, Peter. 2016. “Mind, Matter, and Metabolism:” Journal of Philosophy 113 (10): 481–506. https://doi.org/10.5840/jphil20161131034.

Graziano, Michael. 2013. Consciousness and the Social Brain.

Johansson, Petter, Lars Hall, Sverker Sikström, and Andreas Olsson. 2005. “Failure to Detect Mismatches Between Intention and Outcome in a Simple Decision Task.” Science 310 (5745): 116–19. https://doi.org/10.1126/science.1111709.

Nagel, Thomas. 1974. “What Is It Like to Be a Bat?” The Philosophical Review 83 (4): 435–50. https://doi.org/10.2307/2183914.