How Do Buddhists Define Sentience?

Dakini

Is sentience a simple matter of the presence of a brain or nervous system? (Jellyfish have neither. Are they sentient beings?) Jains define plants as sentient, Buddhists traditionally do not. In what does the quality of sentience lie? What is sentience, and how do we draw the line between sentient beings and non-sentient life?

person

HHDL has said he thinks an ameoba is the simplist form of sentient life, his definition being because it can move around. The question was then asked of him, "What about bacteria?" To which he replied something about they move by chemical processes. It was a fluid discussion and wasn't really fleshed out. He also said he didn't really know but was just making an educated guess.

I think in Buddhism, insects are generally considered to be sentient while plants are not. One definition of sentience being seeking pleasure and avoiding pain. If thats the case though we can clearly see cases of plants doing that, such as a sunflower moving with the sun or there is a type of plant that when you touch it its leaves quickly fold in. Also every plant grows up towards the light and grows roots down into the soil seeking nourishment. If you watch a vine growing in fast motion video it moves remarkably like a worm seemingly seeking out a good path to grow.

[speculation] I wonder if what is needed is nerve cells or a nervous system. Another question I have is if you cut a flatworm into several pieces each piece will grow into a new worm, where is sentience in that case? My hope is that we can definativly prove that mosquitos and ants aren't sentient, but they feel to me as though they are and until its shown they aren't I'll continue to respect them as if they are. [/speculation]

Dakini

HHDL has spoken several times about doing his best to avoid killing mosquitos, so he, at least, defines them as sentient.

I think if we define sentience in terms of a nervous system and/or brain, then we'd have to categorize jellyfish as a type of mobile plant. This is what intrigues me. Personally, I'm fine with defining plants as sentient. Just because they can't move around, doesn't mean they're not sentient, as you pointed out. Does mere mobility imply sentience? This seems to be what it boils down to in the popular mind. Whatever moves around is "animal", what has life but doesn't move around is vegetable, and therefore not sentient. But I'm not sure it's as simple as that.

One dictionary defined sentience as having consciousness. But it also offered the definition of "feeling, vs. thought", which seems a little contradictory. But the root of the word "sentient refers to feeling.

Do plants have consciousness? According to some scientists, everything has at least a rudimentary consciousness, including simple protons, etc. To muddy the waters further, ha.

zenff

Sentience, in my mind, is linked to the idea of qualia; the subjective character of experience.

Although it does not actually mention the word "qualia," Thomas Nagel's paper What Is it Like to Be a Bat?[5] is often cited in debates over qualia. Nagel argues that consciousness has an essentially subjective character, a what-it-is-like aspect. He states that "an organism has conscious mental states if and only if there is something that it is like to be that organism — something it is like for the organism.
http://en.wikipedia.org/wiki/Qualia#The_.22What.27s_it_like_to_be.3F.22_argument

A very, very advanced computer –in theory – can do exactly what we do; but will it have qualia or subjective experience of anything at all?
If not; it’s not sentient.

zenff

What is it like to be a jellyfish? What is it like to be a mosquito?
I’d have to know that before I could say they are sentient or not.

Not a very effective strategy for getting satisfying answers, I’m afraid.

Dakini

haha! ^_^ Nice try, zenff. It's all food for thought
Wouldn't all living things have some rudimentary sense of subjective experience? Plants, as @person pointed out, feel the cool and moist (or too dry) earth, and the warmth (and who knows what else) of the sun. Maybe in the end, the answer is "we don't know" what is sentient and what isn't. We can't know unless we can experience life as the jellyfish, amoeba, and plant experience it.

BonsaiDoug

Must sentient also include being self aware? And would that not draw a more definite line between what is and what is not sentient?

Just wondering.............

person

I think @zenff you hit it on the head. A sentient creature is one that has experience. The problem with that, like you say, is how the heck do we know if something has subjective experience (qualia) or not.

In philosophy there is something called a philosophical zombie this is a creature that acts %100 percent like a creature with consciousness, it even says it has experience, but in fact is completely unconcious. Its a theoretical being used to illustrate what is meant by consciousness.

Subjective experience is so elusive. Here's a couple paragraph's from HHDL in The Universe in a Single Atom.

"A comprehensive scientific study of consciousness must therefore embrace both third-person and first-person methods: it cannot ignore the phenomenological (*study of experience) reality of subjective experience but must observe all the rules of scientific rigor.... here I feel a close collaboration between modern science and the contemplative traditions such as Buddhism, could prove beneficial." p.134

"I believe that it is possible for Buddhism and modern science to engage in collaborative research in the understanding of consciousness while leaving aside the philosophical question of whether consciousness is ultimately physical. By bringing together these two modes of inquiry, both disciplines may be enriched." p.137

Dakini

Is "subjective experience" the same as being "self-aware"?
Is the universe self-aware? There are some books by Amit Goswami that are very interesting: "The Self-Aware Universe", and "Physics of the Soul: The Quantum Book of Living, Dying, Reincarnation, and Immortality". He has a number of interesting titles. Has anyone read these?

Is the Universe sentient?

Thanks, person. I think the mirror test may not be an accurate measure of self-awareness. Are animals aware of their own feelings and thoughts? Do we have any way of knowing? Where is our resident animal psychologist today?

person

Must sentient also include being self aware? And would that not draw a more definite line between what is and what is not sentient?

Just wondering.............

Personally I don't think so. There is something called a mirror test where they place a mark on an animals face and put it in front of a mirror. If the animal reaches for the mark on their own face that is considered a sign of self awarness. Dogs don't pass this test, most animals don't. Apes, dolphins, orcas, elephants and magpies are the only ones that have. So we don't really know where the line is but I'd hope dogs and cats are included.

EDIT: I think this also addresses @Dakini's question.

Dakini

EDIT: I think this also addresses @Dakini's question.

Does it? Just because animals (much less jellyfish and plants) don't recognize themselves in a mirror, does that mean it's ok to kill them, because they're not sentient? Shaky ground, there.

person

EDIT: I think this also addresses @Dakini's question.

Does it? Just because animals (much less jellyfish and plants) don't recognize themselves in a mirror, does that mean it's ok to kill them, because they're not sentient? Shaky ground, there.

I thought I was saying the opposite of that. I started with "personally I don't think so" and ended with "I'd hope dogs and cats are included."

charirama

Who am I?
I am the awareness in which all of this takes place.
I believe that sentience is awareness - no matter how advanced or limited it may be.

I've also had some great discussions about this with one of my Yoga teachers who believes there is no distinction between mind, body and spirit.

Mountains

To me, plants are not sentient (bacteria are in the plant kingdom). Anything in the animal kingdom is. There's plenty of room for discussion on this point however. But we have to draw a line somewhere, otherwise we couldn't eat I'm nothing if not pragmatic.

Dakini

Ah. Bacteria are plants. Amoeba aren't. Thanks for clarifying. : )

person

To me, plants are not sentient (bacteria are in the plant kingdom). Anything in the animal kingdom is. There's plenty of room for discussion on this point however. But we have to draw a line somewhere, otherwise we couldn't eat I'm nothing if not pragmatic.

Actually bacteria aren't in the plant kingdom, they have a kingdom of their own, Monera. And amoeba are in Protcotista. Though I guess there is a two kingdom distinction but I think the 5 kingdom or 6 kingdom is more widely used. One of the distinguishing features of the animal kingdom are nerve cells, so the ability to feel pain or pleasure. That may be a good way of differentiating sentient from non-sentient.

person

Actually, looking into it more I think the 6 kingdoms is the more current model. I remember being taught 5 in school.



So bacteria have 2 different kingdoms, not sure what the difference is.

person

[speculation] I wonder if there is a type of proto consciousness that pervades existence so that everything has some level of sentience, then I wonder if the Buddhist delineation is more about what can feel pain and what can't than about what has experience or not, especially since at the time they didn't have a very sophisticated understanding of living organisms. [/speculation]

suopohe

Ghost have no biological body but they are sentient.

suopohe

In Buddism, Sentient being has ability to experience emotions and has a consciousness.

Dakini

Ghost have no biological body but they are sentient. In Buddism, Sentient being has ability to experience emotions and has a consciousness.

This is interesting. But ghosts are already dead, so we don't have to worry about the 1st precept with them.

Nerve cells. hm. Well, the video said jellyfish don't have a nervous system, I don't know if that means they have no nerve cells...?

I'm starting to conclude that sentience is a combination of ability to feel pain (nerve cells or systems) plus consciousness/awareness. Lots of good feedback here, great discussion, everyone. :thumbsup:

Jason

There are two main terms I'm aware of, pana and satta. The Pali term pana means 'that which breathes,' and according to Bhikkhi Bodhi, denotes "any living being that has breath and consciousness." The Pali term satta is often translated as 'being,' and specifically denotes one caught up in "any desire, passion, delight, or craving" for the five aggregates (SN 23.2). As for sentience, I'd say that any living being with at least some level of consciousness, which itself is conjoined with feelings and perceptions (MN 43), can and should be considered sentient. The difficultly, however, is trying to determine whether a particular being, organism, etc. posseses consciousness, especially at a rudimentary level. Any kind of organism that seems to intend, react to pain, etc. would most likely qualify, in my opinion. Beyond that, I'm unsure.

Jason

I'm starting to conclude that sentience is a combination of ability to feel pain (nerve cells or systems) plus consciousness/awareness. Lots of good feedback here, great discussion, everyone. :thumbsup:

It should also be noted that in Buddhism feelings aren't necessarily limited to bodily feelings, so it's theoretically possible for non-material beings, such as those that are said to inhabit the immaterial world or formless realm (arupa-loka), to experience mental feelings, assuming such beings exist.

That said, I think most of what's known as the '31 planes of existence' has been cobbled together from various sources throughout the canon. For example, the four formless realms may have originally referred to advanced states of meditative absorption since they correspond to the four 'immaterial' jhanas, but were later taken to also refer to actual realms of birth above the brahma-realms, especially for the benefit of non-returners.

Mountains

In Buddism, Sentient being has ability to experience emotions and has a consciousness.

There are people who will argue that no animal other than a human can experience emotion. I think that's total hogwash, but there are people who firmly believe it.

person

There are two main terms I'm aware of, pana and satta. The Pali term pana means 'that which breathes,' and according to Bhikkhi Bodhi, denotes "any living being that has breath and consciousness."

Interesting, I wonder how breath gets defined? For example insects don't have lungs so they don't "breathe" but they do transport oxygen through their cells kind of by a process of diffusion through the cell walls and a series of tubes which they can control. So is it any creature that uses an oxygen exchange to support its life?

Ghost have no biological body but they are sentient.

Good point.

Mountains

Interesting, I wonder how breath gets defined? For example insects don't have lungs so they don't "breathe" but they do transport oxygen through their cells kind of by a process of diffusion through the cell walls and a series of tubes which they can control. So is it any creature that uses an oxygen exchange to support its life?

Your definition of "breathing" makes the difference. If you define it one way, then certainly insects breathe. They just don't happen to have lungs to do it with. They do respire though (ever seen their abdomen heaving?). If you define it another way, then even plants breathe, since they take in gasses, exchange them on the cellular level, and expel the resulting gas. I don't think breathing is a test of sentience.

person

In Buddism, Sentient being has ability to experience emotions and has a consciousness.

This is the hard part though, how do we tell which beings experience emotions and have consciousness? If you just look at behavior even plants have behaviors that seem to seek pleasure and avoid pain, such as a sunflower following the sun. So what other criteria can we use? I guess mostly the question concerns animals since we don't really have any actual experience of any other types of beings.

Jason

There are two main terms I'm aware of, pana and satta. The Pali term pana means 'that which breathes,' and according to Bhikkhi Bodhi, denotes "any living being that has breath and consciousness."

Interesting, I wonder how breath gets defined? For example insects don't have lungs so they don't "breathe" but they do transport oxygen through their cells kind of by a process of diffusion through the cell walls and a series of tubes which they can control. So is it any creature that uses an oxygen exchange to support its life?

Ghost have no biological body but they are sentient.

Good point.

As far as I understand it, the term pana (or prana in Sanskrit) has a fairly broad meaning, and isn't just limited to things with lungs that resire. It all stems from how ancient Indian religions and philosophies viewed life, and breathe was the main symbol or representation of life or of life energy. Insects would certain qualify as having life energy from this point of view, and I'd hazard to guess that any organism that respires and/or metabolizes would as well. I think that's why some groups included plants as living and sentient beings while others didn't due to apparent lack of mind (i.e., consciousness, perception, feelings, and intention).

charirama

The Hard Problem
How does something as immaterial as consciousness arise from something as unconscious as matter?
David Chalmers
Prof Philosophy
Univ Arizona

person

There are two main terms I'm aware of, pana and satta. The Pali term pana means 'that which breathes,' and according to Bhikkhi Bodhi, denotes "any living being that has breath and consciousness."

Interesting, I wonder how breath gets defined? For example insects don't have lungs so they don't "breathe" but they do transport oxygen through their cells kind of by a process of diffusion through the cell walls and a series of tubes which they can control. So is it any creature that uses an oxygen exchange to support its life?

Ghost have no biological body but they are sentient.

Good point.

As far as I understand it, the term pana (or prana in Sanskrit) has a fairly broad meaning, and isn't just limited to things with lungs that resire. It all stems from how ancient Indian religions and philosophies viewed life, and breathe was the main symbol or representation of life or of life energy. Insects would certain qualify as having life energy from this point of view, and I'd hazard to guess that any organism that respires and/or metabolizes would as well. I think that's why some groups included plants as living and sentient beings while others didn't due to apparent lack of mind (i.e., consciousness, perception, feelings, and intention).

Yeah, this is where the distinction gets tricky for me. Plants do many of the things we attribute to a sentient, feeling being, but in Buddhism they aren't considered sentient. An apparent lack of mind seems to be the distinguishing feature, but how can we tell what has mind and what doesn't?

person

The Hard Problem
How does something as immaterial as consciousness arise from something as unconscious as matter?
David Chalmers
Prof Philosophy
Univ Arizona

A David Chalmers reference. :thumbsup:

Jason

Yeah, this is where the distinction gets tricky for me. Plants do many of the things we attribute to a sentient, feeling being, but in Buddhism they aren't considered sentient. An apparent lack of mind seems to be the distinguishing feature, but how can we tell what has mind and what doesn't?

It really all depends on how you define your terms and the criteria you wish to set.

possibilities

Sentient sunflowers? I believe the turning with the sun is an evolved pattern, simply for the sake of growth and survival of this particular species. IMO all plants react to light - or lack of light - in their natural growth. It's a biological REACTION, not a choice... I doubt the plant will move its head if the sun is absent.

Instinct and survival behavior that has developed over 100os of years may need to be considered if you talk about consciousness.... IMO, thinking has to with choice and selective, purposeful behavior.
Feeling not so much, it may be more of a reflex like cause and effect, and maybe developed in response to survival skills, esp in animals.... not sure where that leaves this criteria for this discussion......

person

Sentient sunflowers? I believe the turning with the sun is an evolved pattern, simply for the sake of growth and survival of this particular species. IMO all plants react to light - or lack of light - in their natural growth. It's a biological REACTION, not a choice... I doubt the plant will move its head if the sun is absent.

Instinct and survival behavior that has developed over 100os of years may need to be considered if you talk about consciousness.... IMO, thinking has to with choice and selective, purposeful behavior.
Feeling not so much, it may be more of a reflex like cause and effect, and maybe developed in response to survival skills, esp in animals.... not sure where that leaves this criteria for this discussion......

My point wasn't to say that sunflowers are sentient, it was to ask how do we differentiate that type of stimulus response behavior from that of a mosquito? I doubt in a mosquito there's much conscious choice about whether to suck some blood from this warm body or to go find a different one.

So maybe in a mosquito there is some kind of basic cognition that determines whether an object is good to eat and a sunflower has no cognition and is merely, completely without conciousness, reacting to a stimulus. The question is, how can we tell the difference and define sentience?

Jason

Sentient sunflowers? I believe the turning with the sun is an evolved pattern, simply for the sake of growth and survival of this particular species. IMO all plants react to light - or lack of light - in their natural growth. It's a biological REACTION, not a choice... I doubt the plant will move its head if the sun is absent.

Instinct and survival behavior that has developed over 100os of years may need to be considered if you talk about consciousness.... IMO, thinking has to with choice and selective, purposeful behavior.
Feeling not so much, it may be more of a reflex like cause and effect, and maybe developed in response to survival skills, esp in animals.... not sure where that leaves this criteria for this discussion......

My point wasn't to say that sunflowers are sentient, it was to ask how do we differentiate that type of stimulus response behavior from that of a mosquito? I doubt in a mosquito there's much conscious choice about whether to suck some blood from this warm body or to go find a different one.

So maybe in a mosquito there is some kind of basic cognition that determines whether an object is good to eat and a sunflower has no cognition and is merely, completely without conciousness, reacting to a stimulus. The question is, how can we tell the difference and define sentience?

One way is by the nature and level of reaction involved, particular with regard to volition. Insects can at least be observed to have what appears to be a higher level of volition than flowers. It can be argued, for example, that flowers grow towards sunlight and photosynthesize automatically, whereas insects can go to and fro, eat, hide, etc. of their own volition.

person

One way is by the nature and level of reaction involved, particular with regard to volition. Insects can at least be observed to have what appears to be a higher level of volition than flowers. It can be argued, for example, that flowers grow towards sunlight automatically, whereas insects can go to and fro, eat, hide, etc. of their own volition.

This is a good point, but that brings up another question. What about ameoba or bacteria? HHDL said he thought that maybe ameoba were sentient, likely based on the criteria you stated above. From a Buddhist perspective then, does that mean if we have some kind of ameobic infection (ameobic dysentery) or maybe even a bacterial one that we are then breaking the first precept by taking medicine to cure ourselves?

possibilities

volition = choice (see my post above: "all plants react to light - or lack of light - in their natural growth. It's a biological REACTION, not a choice...") --meaning insects/animals/humans etc make choices

just sayin' :-)

Jason

This is a good point, but that brings up another question. What about ameoba or bacteria? HHDL said he thought that maybe ameoba were sentient, likely based on the criteria you stated above. From a Buddhist perspective then, does that mean if we have some kind of ameobic infection (ameobic dysentery) or maybe even a bacterial one that we are then breaking the first precept by taking medicine to cure ourselves?

Possibly. But the precepts seem to leave room for these kinds of things. For one, bacteria that cause diseases aren't often perceive as living beings, and as Bhikkhu Bodhi notes in his tract, "Taking the Precepts," a full violation of the first precept involves five factors: (1) a living being; (2) the perception of the living being as such; (3) the thought or volition of killing; (4) the appropriate effort; and (5) the actual death of the being as a result of the action. Therefore, if there's no perception of a living being, only an illness that's treatable by medicine given to you by a doctor, then there's no violation of the first precept, or at least not a full one.

In addition, I think Susan Jootla brings up a good point about the importance of the intention behind such actions as making, prescribing, and taking things like antibiotics in her essay, "Right Livelihood: The Noble Eightfold Path in the Working Life":

If we manufacture, deal in, or use insecticides or other kinds of poisons in our work, we are engaging to some degree in wrong livelihood because here, too, we are breaking the First Precept and directly encouraging others to do so as well. However, the motivation behind the use of such material has a great deal to do with the depth of the kamma being created. A doctor rightly gives drugs which are harmful to bacteria and viruses, not because he hates the "bugs," but in order to help cure the human being. Here the good more than balances the bad. But if we go about applying poison to rat-holes and cockroaches' hideouts with anger or aversion toward the pests, we would be generating considerably strong bad kamma.

person

volition = choice (see my post above: "all plants react to light - or lack of light - in their natural growth. It's a biological REACTION, not a choice...") --meaning insects/animals/humans etc make choices

just sayin' :-)

Ok, I guess I'm just not so convinced that insects are making choices and aren't just reacting.

Also if you bring biological determinism into the picture aren't we all just reacting to conditions and choice is an illusion. (Not that this is what I believe)

person

@Jason Thanks for your arguments they are very helpful. Just to push the point some more though; "(2) the perception of the living being as such;" does this mean I shouldn't try to figure out if bacteria are sentient so I can live in ignorance and thus not have to potentially create any negative karma?

Jason

@Jason Thanks for your arguments they are very helpful. Just to push the point some more though; "(2) the perception of the living being as such;" does this mean I shouldn't try to figure out if bacteria are sentient so I can live in ignorance and thus not have to potentially create any negative karma?

That's entirely up to you. As for myself, I accept that I'm most likely going to do some amount of harm since life is complicated and nobody's perfect; although I try to do my best to limit that amount by making sure my intentions are as skillful and as harmless as possible without unduly harming myself.

person

@Jason Thanks for your arguments they are very helpful. Just to push the point some more though; "(2) the perception of the living being as such;" does this mean I shouldn't try to figure out if bacteria are sentient so I can live in ignorance and thus not have to potentially create any negative karma?

That's entirely up to you. As for myself, I accept that I'm most likely going to do some amount of harm since life is complicated and nobody's perfect; although I try to do my best to limit that amount by making sure my intentions are as skillful and as harmless as possible without unduly harming myself.

Beautiful. Thanks for the overall contribution, really helpful.