I’ll admit I didn’t really follow the section ‘sensation, sentition, and the ipsundrum’ but the rest of it seems very weak, if any, evidence for the theory.
To pick one example: Why should I think sensory play is a necessary condition for sentience?
You could imagine a species which had all the neural architecture mammals & birds have, but had no limbs. I think we wouldn’t observe it ‘playing,’ but I think Humphrey’s theory still implies it’s sentient.
I’ve tried to condense a book-length presentation into a 10 minute read and I probably have made some bad choices about which parts to leave out.
Its not that sensory play is necessary for producing sentience. The claim is that any animal that is sentient would be motivated to play. There might be other motivations for play that are not sentience, but all sentient creatures (so the argument goes) would want to play in order to explore and learn about the properties of its own sensory world.
For the limbless species you mentioned, if we imagine a radical scenario like a mammal that evolves into an entirely static plant-like existence, but for some reason, it doesn’t lose its now-evolutionarily-useless capacity for sentience, i suppose I imagine that it would play if it could, but does not because it can’t. So perhaps you could rescue Humphrey’s assertion about play by modifying it to “any sentient animal will be motivated to play and will play to the extent they are physically able to do so”.
The theory depends on humans shared ancestry and neurophysiology with other animals. Conditional on shared ancestry and neurophysiology we are able to make some tentative inferences about animal experience from our own experiences. Without that shared ancestry, I think he would be far too far out on a limb (heh).
That makes sense — I appreciate you doing that work & making calls about what to include; I bet there’s a lot I’m missing!!
Ah, I wrote & meant ‘a necessary condition for’ — I hadn’t misunderstood the argument in the way you’re worried about in your second paragraph (but perhaps a useful clarification for anyone reading!)
My problem is I don’t buy that ‘any animal that is sentient would be motivated to play’ — and ultimately I think the additional explanation you’ve provided here, about shared ancestry and neurophysiology, is interesting & relevant to think about re: which if any animals are sentient, but I think it just boils down to:
Humans are sentient
Humans have a shared ancestry and neurophysiology with other animals
?(Sentience depends on neurophysiology)? [fn]
C. Other animals are likely to be sentient
C2. Other animals are more likely to be sentient in accordance with the extent to which they share human ancestry and neurophysiology.
This argument, while IMO important/pretty compelling as a reason to start of with some moderate credence on animal sentience, doesn’t do that much, and certainly couldn’t, on its own, convince me of any necessary conditions for sentience — certainly not sensory play.
It also doesn’t do anything to convince me that non-bird non-mammals are sufficiently different (in terms of shared ancestry and neurophysiology) from humans, such that we should think they’re not sentient.
[fn] I’m unsure from your summary if Humphrey means to claim this or not, sorry!
To give a concrete example, my infant daughter can spend hours bashing her toy keyboard with 5 keys. It makes a sound every time. She knows she isn’t getting any food, sleep, or any other primary reinforcer to do this. But she gets the sensations of seeing the keys light up and a cheerful voice sounding from the keyboard’s speaker each time she hits it. I suppose the primary reinforcer just is the cheery voice and the keys lighting up (she seems to be drawn to light—light bulbs, screens, etc).
During this activity, she’s playing, but also learning about cause and effect—about the reliability of the keys reacting to her touch, about what kind of touch causes the reaction, and how she can fine-tune and hone her touch to get the desired effect. I think we can agree that many of these things are transferable skills that will help her in all sorts of things in life over the next few years and beyond?
I’m sort of conflating two things that Humphrey describes separately: sensory play, and sensation seeking. In this example it’s hard to separate the two. But Humphrey ties them both to consciousness, and perhaps there’s still something we can learn from about an activity that combines the two together.
In this case, the benefits of play are clear, and I guess the further premise is that consciousness adds additional motivation for sensory play because, e.g., it makes things like seeing lights, hearing cheery voices much more vivid and hence reinforcing, and allows the incorporation of those things with other systems that enable action planning about how to get the reinforcers again, which makes play more useful.
I agree this argument is pretty weak, because we can all agree that even the most basic lifeforms can do things like approach or avoid light. Humphrey’s argument is something like the particular neurophysiology that generates consciousness also provides the motivation and ability for play. I think I have said about as much as I can to repeat the argument and you’d have to go directly to Humphrey’s own writing for a better understanding of it!
Yes I see that is a reasonable thing to not be convinced about and I am not sure I can do justice to the full argument here. I don’t have the book with me, so anything else I tell you is pulling from memory and strongly prone to error. Elsewhere in this comments section I said
When you have sensations, play can teach you a lot about your own sensory processes and subsequently use what you’ve learned to leverage your visual sensations to accomplish objectives. It seems odd that an organism that can learn (as almost all can) would evolve visual sensations but not a propensity to play in a way that helps them to learn about those sensations.
And
Humphrey theorises that the evolutionary impulse for conscious sensations includes (1) the development of a sense of self (2) which in turn allows for a sense of other, and theory of mind. He thinks that mere unconscious perception can’t be reasoned about or used to model others because, being unconscious, it is inaccessible by the global workspace for that kind of use. in contrast, conscious sensations are accessible in the global workspace and can be used to imagine the past, future, or what others are experiencing. The cognitive and sensory empathy that allows can enable an organism to behave socially, to engage in deceit or control, to more effectively care for another, to anticipate what a predator can and can’t see, etc.
I believe the idea is something like sentience enables a lot more opportunity to learn about the world, and learning opportunities can be obtained through play. Not taking those opportunities if you’re able is sort of like leaving free adaptive money on the table.
Thanks for your summary!
I’ll admit I didn’t really follow the section ‘sensation, sentition, and the ipsundrum’ but the rest of it seems very weak, if any, evidence for the theory.
To pick one example: Why should I think sensory play is a necessary condition for sentience?
You could imagine a species which had all the neural architecture mammals & birds have, but had no limbs. I think we wouldn’t observe it ‘playing,’ but I think Humphrey’s theory still implies it’s sentient.
I’ve tried to condense a book-length presentation into a 10 minute read and I probably have made some bad choices about which parts to leave out.
Its not that sensory play is necessary for producing sentience. The claim is that any animal that is sentient would be motivated to play. There might be other motivations for play that are not sentience, but all sentient creatures (so the argument goes) would want to play in order to explore and learn about the properties of its own sensory world.
For the limbless species you mentioned, if we imagine a radical scenario like a mammal that evolves into an entirely static plant-like existence, but for some reason, it doesn’t lose its now-evolutionarily-useless capacity for sentience, i suppose I imagine that it would play if it could, but does not because it can’t. So perhaps you could rescue Humphrey’s assertion about play by modifying it to “any sentient animal will be motivated to play and will play to the extent they are physically able to do so”.
The theory depends on humans shared ancestry and neurophysiology with other animals. Conditional on shared ancestry and neurophysiology we are able to make some tentative inferences about animal experience from our own experiences. Without that shared ancestry, I think he would be far too far out on a limb (heh).
That makes sense — I appreciate you doing that work & making calls about what to include; I bet there’s a lot I’m missing!!
Ah, I wrote & meant ‘a necessary condition for’ — I hadn’t misunderstood the argument in the way you’re worried about in your second paragraph (but perhaps a useful clarification for anyone reading!)
My problem is I don’t buy that ‘any animal that is sentient would be motivated to play’ — and ultimately I think the additional explanation you’ve provided here, about shared ancestry and neurophysiology, is interesting & relevant to think about re: which if any animals are sentient, but I think it just boils down to:
This argument, while IMO important/pretty compelling as a reason to start of with some moderate credence on animal sentience, doesn’t do that much, and certainly couldn’t, on its own, convince me of any necessary conditions for sentience — certainly not sensory play.
It also doesn’t do anything to convince me that non-bird non-mammals are sufficiently different (in terms of shared ancestry and neurophysiology) from humans, such that we should think they’re not sentient.
[fn] I’m unsure from your summary if Humphrey means to claim this or not, sorry!
To give a concrete example, my infant daughter can spend hours bashing her toy keyboard with 5 keys. It makes a sound every time. She knows she isn’t getting any food, sleep, or any other primary reinforcer to do this. But she gets the sensations of seeing the keys light up and a cheerful voice sounding from the keyboard’s speaker each time she hits it. I suppose the primary reinforcer just is the cheery voice and the keys lighting up (she seems to be drawn to light—light bulbs, screens, etc).
During this activity, she’s playing, but also learning about cause and effect—about the reliability of the keys reacting to her touch, about what kind of touch causes the reaction, and how she can fine-tune and hone her touch to get the desired effect. I think we can agree that many of these things are transferable skills that will help her in all sorts of things in life over the next few years and beyond?
I’m sort of conflating two things that Humphrey describes separately: sensory play, and sensation seeking. In this example it’s hard to separate the two. But Humphrey ties them both to consciousness, and perhaps there’s still something we can learn from about an activity that combines the two together.
In this case, the benefits of play are clear, and I guess the further premise is that consciousness adds additional motivation for sensory play because, e.g., it makes things like seeing lights, hearing cheery voices much more vivid and hence reinforcing, and allows the incorporation of those things with other systems that enable action planning about how to get the reinforcers again, which makes play more useful.
I agree this argument is pretty weak, because we can all agree that even the most basic lifeforms can do things like approach or avoid light. Humphrey’s argument is something like the particular neurophysiology that generates consciousness also provides the motivation and ability for play. I think I have said about as much as I can to repeat the argument and you’d have to go directly to Humphrey’s own writing for a better understanding of it!
Yes I see that is a reasonable thing to not be convinced about and I am not sure I can do justice to the full argument here. I don’t have the book with me, so anything else I tell you is pulling from memory and strongly prone to error. Elsewhere in this comments section I said
And
I believe the idea is something like sentience enables a lot more opportunity to learn about the world, and learning opportunities can be obtained through play. Not taking those opportunities if you’re able is sort of like leaving free adaptive money on the table.