At the Francis Crick Memorial Conference in Cambridge last month, a collection of internationally recognized experts on consciousness took an unusual step, as science conferences go: they issued a declaration (pdf). The subject was whether or not non-human animals could be considered “conscious.” (See discussion by Octopus Chronicles, Christof Koch, io9.) The spirit of the declaration was in the direction of saying “pretty much, yeah,” although they tried to stick to what could be scientifically discussed. Here’s the upshot of the declaration:
The absence of a neocortex does not appear to preclude an organism from experiencing affective states. Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviors. Consequently, the weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Nonhuman animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.
Even the experts don’t necessarily agree on a definition of “consciousness,” so the declaration doesn’t come right out and say “animals are conscious.” But the authors basically agree that the mental supervenes on the physical, so whatever consciousness may be, it must have some neurological substrate — some parts of the brain that do the work. The point they’re making is, whatever those parts are, some animals have them too.
I don’t have a well-thought-out position on this, at least as far as the big-picture consequences are concerned. Obviously human beings are animals, so we shouldn’t be surprised that we share neurological workings. And obviously (I would argue) consciousness is not located somewhere simple and discrete in the brain (like the pineal gland) — it has grown up gradually, and makes use of various parts of the brain, so it’s not surprising to find aspects of consciousness involving pre-cortical structures. We are part of the evolution of the biosphere, not something standing outside of it.
On the other hand, whether it’s qualitative or merely quantitative, there is something different about human beings. We’re the only species that builds cars, if you want a blunt way of putting it. We’re the only species that sets up political action committees, and does contour integration. (Usually not at the same time.) The human brain seems to represent some kind of phase transition with respect to the brains of non-human animals. It might be a gradual, second-order transition, or it might be an abrupt, first-order transition. We don’t really know, and that’s why it’s important to tackle these difficult scientific questions (and not make up our minds about the answers ahead of time).
The real-world question is how our increasing understanding of the relationship between human and animal neurology should affect how we treat non-human animals. It’s not an easy one, and saying “they’re not people so we can do whatever we want” or “humans are just animals and we should treat every animal with equal dignity” both seem like simplistic cop-outs to me. I’m just glad the science is moving forward, so we can increasingly base our behaviors on reality rather than on vague guesses.
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OK. Here’s how I would put it. Consciousness is the ability to experience qualia. But that’s both redundant and not even all that informative. “qualia” is defined (by my Google browser dictionary) as “The internal and subjective component of sense perceptions, arising from stimulation of the senses by phenomena.” So what that really says is that consciousness is the ability to have subjective experiences. I’m happy with that definition.
But what does that mean? How can we define subjective experience? How can we test to see whether something has subjective experiences? As far as I know, we can’t answer those questions in any useful way. See, for example, the case of Mary, the colorblind neuroscientist at the start of section 2 here: http://goo.gl/oJ04t.
I would say that all that is very different from the ability to think. Being able to do contour integrals has nothing to do with consciousness in my opinion. So I would make a sharp distinction between subjective experience and the ability to manipulate complex abstractions. The former has to do with consciousness; the latter doesn’t.
Part of the declaration said, “Convergent evidence indicates that non-human animals have…the capacity to exhibit intentional behavior.” How does that impact recent arguments against the existance of free will?
Anyone who has a dog as a pet knows the obvious answer to this question. As for thinking consider a dog like a one or two year old infant. Can infants do contour integrals? Not many. Are they conscious?
Ask any parent.
@karaktur. The appearance of intentional behavior can be misleading. Consider plants that turn toward the sun or bacteria (which are single cells) that swim upstream in a nutrient gradient. Intentional behavior? Sure looks like it, but it’s hard to make a case for consciousness.
I’m almost sure you used “conscious” when you really meant “sentient” or “self-aware”. Most animals are conscious for most hours of the day(except for cats, who are usually dreaming).
By the way, if you ever find yourself getting caught up on whether animals have emotions or not, it’s a sign that you have a philosophy growth that you should probably have checked.
dearest karaktur: Proponents of free will must first develop an argument FOR free will since that is the extraordinary claim that demands evidence. Intentional behavior can be shown with (of course) the Trolley Problem to be volitional — making a choice between two horrible outcomes — but not free in any sense. I don’t want anyone to die in a Trolley accident and if I could arrange that outcome I would claim free will. But we never have three wishes from the free will genie. All we can do is behave in a way that maximizes least worse outcomes. An octopus ‘intends’ to hide itself under an empty half of a coconut (i.e. it acts as if it desired certain outcomes only available under coconuts) so that it can catch prey. But when selection pressure removes the non-coconut wielding octopus from the local environment the illusion of free will disappears. Among the coconut wielding octopi there are those that wear coconuts smartly — their volitional behavior is more fit — and those that screw it up by trying to have sex under a coconut etc.. Again, selection pressure favors the octopi with smarts. But making constrained choices that force us to kill at least one worker with a trolley (or five) or put a coconut on our head (or not) does not seem like the kind of free will anyone really wants.
Thank you Professor Carroll for bringing up the question.
Is there some implication here that without this ill-defined “consciousness,” we would have a right to do with animals as we wish? Is there an implication by the “consciousness experts” that by granting “consciousness” to animals they will spend a penny more per pound to treat animals with an ounce less “inhumanity” in how they are raised and killed? Can we eat people incapable of performing contour integrals? Surely most puppies display more joy in living than most human beings. If we look at the recent history of humans who thought they had a right to enslave other humans of a different color one questions the rationalizations of humans, or at least some humans. One wonders if such humans act in a conscious manner themselves if “consciousness” includes the capability to consider the rights of humans and other sentient beings.
If we needed to eat animals to survive that would be one thing, though it still wouldn’t justify poor treatment. Vegans seem to be thriving with a plethora of delicious and healthy alternatives.
As the philosopher Jeremy Bentham wrote in “Principles of Morals and Legislation”:
“The question is not, can they reason? Nor, can they talk? But can they suffer?”
@DavidWonderland
I would say that most domesticated animals have better reasoning abilities than a lot of two-year-old humans. They understand a language completely foreign to them and can associate certain words with expected behavior, they can reason out and solve simple problems such as moving a blanket in order to get at a toy underneath it, birds and primates use tools. Yes, they are sentient and “conscious.” I’m convinced they’re aware of “self” and “other,” although that’s only from personal experience with dogs. They mourn the loss of loved ones. Do they contemplate philosophical issues and mathematical concepts? Probably not, but then neither do a lot of people I know.
In fact, I’d say that without our ability to share previous generation’s knowledge through language, humans would still be operating on what would be considered animal level.
So… if there are non-human animals(;-)?) then there are definitely some human animals, right?
Who came up with this stupid terminology?
so ghandi was right?
I like the last paragraph, but….
The “hard problem” of consciousness, as defined by Chalmers, is much more difficult than presented here. We cannot say that animals have consciousness, because one can only experience one’s own perceptual bubble. “I” cannot even say that “you” are conscious. “I think, therefore I am”, is a valid conclusion. For me to say “you think, therefore you are” is pure speculation.
“We’re the only species that builds cars, if you want a blunt way of putting it. We’re the only species that sets up political action committees, and does contour integration. (Usually not at the same time.) ”
Im not sure what point is being made here. Are you suggesting that animals dont use tools? They do.
Are you suggesting animals dont engage in politics? they do
Most people cant do countour intergtaion but animals can do some maths.
Of course Im not saying animals are the same as humans but the differences are harder to define than most people think.
i think the way humans treat animals is disgraceful and part fo the reason for that is religion telling us animals were made for us and others saying animals are not self aware but statements are baseless.
it seems to me man’s mind can never fully understand consciousness only notice different levels of it. The source of any level of consciousness is the same source for all animals and all forms around us.To understand we would have to be the creator.The brain which is the tool man uses to logic ,learn and understand was created thru evoloution on this planet and has been developing for zero to its present form for 4.5 billion years. The source that created all life on this earth is the sun.Turn the switch off on the sun and all forms return to energy. Before the sun existed the universe existed ( as science tells us for 9 billion years before earth existed) so consciousness which is energy has been and will be around and creating forever. Humans are just one form created by it and on this planet at this time apparently the highest level.However we all are comprised of some form of it so we are all inner connected and that in my opinion is why dogs and other so called lower animals have the ability to undestand humans feelings as in essence we are all interconnected to one degree or another.
I wonder why there’s such an insistence on limiting “consciousness” (whatever that may be) to organisms with particular _neurological_ substrates. Yes, the “mental” supervenes on the physical, but surely it’s the interconnections & interactions between neurons that are relevant, not the fact that they are neurons per se? In which case, why not think of consciousness as an emergent phenomenon supervening on any physical substrate with a sufficiently complex interconnections or a particular kind of network topography or something?
For a super-fun (hard sci-fi) take on intelligence sans consciousness, let me recommend Peter Watts’ “Blindsight”.
Since no one has mentioned the idea of being self-aware in regard to consciousness I guess it is up to me. It seems to me that humans are the only ones who actually think about being conscious, or wonder who else might be. Is that a definition of being conscious? Humans are the only ones who seem to be interested in building cars in the first place. Why would a bison be interested in a car anyway? Are we missing the physiological piece of the puzzle, by ignoring the fact that animals are observed by humans using the only tools that they are able to manipulate? If we made prosthetic limbs for a crow, could he become a locksmith? A TV repaircrow? Or is the important thing whether or not he knows he will die after a life of twenty years? Does he care about it?
Why is a “declaration” necessary? It seems like the promulgation of a papal decree on a scientific question. Tacky.
The problem is that there are no “internationally recognized experts on consciousness”, only internationally recognized people who talk about consciousness. Because, at the neural level, we have zero knowledge — none — of the neural substrates of consciousness. There are theories, but there is no evidence. I say this as a neuroscientist. It’s certainly fair to say that no neural structure leaps out at you as uniquely human that would say, “this is the qualitatively different thing that makes humans and only humans conscious”. The obvious differences are quantitative, not qualitative. If we have consciousness, I’d certainly bet that many other animals do as well. But until we know something scientifically about consciousness, we really can’t say anything scientifically about consciousness.
If you define the old traits, they seem to be following down the usual arguments,
Humans communicate, well so do the other animals.
Humans use tools to build things, well so do the other animals.
So I negate this following argument:
” We’re the only species that builds cars, if you want a blunt way of putting it. We’re the only species that sets up political action committees, and does contour integration. (Usually not at the same time.) The human brain seems to represent some kind of phase transition with respect to the brains of non-human animals.”
it’s just a gray scale. Car vs. beaver dam, vs. Bowerbird construction, all the same.
Humans can recognize themselves, well yes other animals can as well.
So the question is, what is it *exactly* that we can do, that a different animal can not. (And I don’t mean build an airplane, or download videos -that is an extrapolation of abilities.)
Seems we have many necessary requirements to define a conscious being,
but no necessary and sufficient criterion to define a conscious being.
[Reminds me of quantum mechanical correlations, there are necessary constraints (e.g. Tsirelon’s bound) but
no necessary and sufficient criterion. So QM and consciousness, in the same boat. Work to do, work to do.]
When I was trying to nurse a baby turtle back to health I fed it meal worms. This was fine as long as I kept them in the refrigerator. Once I let them warm up and when I tried to feed one to my turtle, it squirmed away as frantically as physicist trying to dodge an oncoming train. I can’t be sure what went on in his tiny insect brain, but I am sure that he recognized his oncoming doom and frantically tried to escape it.
If they have a brain, they are probably conscious, at least to an extent.
@10. Michael Says:
“So… if there are non-human animals(;-)?) then there are definitely some human animals, right?
Who came up with this stupid terminology?”
I suggest you study set theory.
@17 Elizabeth Davies: “It seems to me that humans are the only ones who actually think about being conscious, or wonder who else might be.” How do you know? I have enough difficulty figuring out what other humans think about, let alone other animals…
@19 Ken Miller: I agree completely!
Me too. I agree.
The only important difference between humans and other mammals is the capacity for complex symbolic communication. Everything else – science, technology, politics, culture – follows from that.