The question has been changed to one that makes no sense. The question is now a redundancy as all persons are sentient.

The original question was, “What is a sentient being?”

The answers given by others here are scary. It is hard to believe that so many people have so little basic knowledge.

A “sentient” creature is any creature that feels and experiences: color, taste, sound, smell, pain, pleasure, emotions, thoughts or any subjective experience.

Physics can’t account for sentience. Just fifty years ago, scientists were saying cats and dogs were not sentient, and said anyone making the claim they were was engaging in the “pathetic fallacy.”

Sentience is related to the senses.

In humans, each sense has its own lobe in the brain that creates it. The is the visual cortex, the auditory lobe, the olfactory lobe, thr gustatory lobe, the spatial lobe, and the temporal lobe. And then there is the love that receives electrical signals sent from nerve endings embedded in our flesh.

What we experience as space and time are created by lobes in our brain and only crudely correlate with reality.

The lobe responsible for human thought and intelligence is independent of the lobes that process and create our senses and feelings.

Sentience is not something that can be adequately defined since we wouldn’t know such a thing exists if we ourselves were not sentient.

Sentience is not physical or material. Its existence gives rise to the belief in a soul and spiritual worlds. Though, there is no evidence for this.

Sentience gives rise to the concept of mind-body dualism. Our brains create beings and minds that feel.

Sentience is probably a spectrum condition requiring a central nerve center, and sufficient neural complexity.

Tropic and reflex responses are not an indication of sentience.

People often confuse life with sentience. It is highly unlikely single-celled orgasms, plants, jellyfish, bacteria, and viruses are sentient.

Plants could feel pain, but there is zero evidence that they do because they lack a central nervous system that is critical for the creation of sentience in animals

Are worms sentient? Are fish sentient? Most fish have nociceptors which in humans send pain signals to the brain. However, pain is actually created in one part of the human brain, and felt in another.

Do fish have brains capable of generating of generating sensations, then feeling them? If fish feel pain is it in any way comparable to human pain?

Each of our senses is produced by a specific lobe in our brains in response to electrical signals sent to them from our sensory organs.

Then somehow these lobes send signals to our conscious minds where they are felt and experienced. The conscious, sentient part of our brain is who we really are, not the lobes that create the sensations.

During non-REM sleep we temporarily cease to exist, we feel nothing, and are not sentient. Though, the slightest sensation make activate some level of consciousness and sentience.

When an unconscious part of our brain detects light, sound or motion, it wakes us up. This detector is more sensitive in some people who are light sleepers.

Somehow, the sentient, conscious part or parts of our brain do something very special, almost magical. They ”feel” and experience a virtual reality.

Atoms and clusters of atoms should not feel anything no matter how complex they are arranged.

Computers will never be sentient.

Computers mimic the part of our brains that compute and calculate, not the part that feels. It is not our intelligence that makes us sentient.

A person with sufficient brain damage may have zero intelligence but may still be able to feel a lot of pain.

Intelligence is what differentiates us from other animals, sentience is what differentiates us from plants, vegetables, robots.

A computer with infinite intelligence would not understand what humans mean by the color red or by pain, or by love. These are not physical phenomena. They are called “qualia.”

Physicists study the objective universe: matter-energy and space-time. But we only experience and feel sensations created by our brains. We never “see” the real universe.

According to all known laws of physics, we shouldn’t exist. Physics can’t even tell us what we are. Thoughts, feelings, emotions and sensations are not matter, energy, subatomic particles, strings or branes.

We can’t even know with 100% certainty that a physical universe exists at all because we never directly observe it. We naturally assume a physical universe exists. People who believe in God might say God creates all our experiences.

This doesn’t seem very plausible for a number of reasons, but it can’t be ruled out. Physicists are able to explain 98% of what we experience, except it can’t explain why we experience anything at all, and what exactly our experiences really are.

There is an entire realm of reality that physics can’t detect or measure, and that reality is more relevant to us than the one physics knows about.

It is total absence of knowledge of what our minds, sensations, feelings and experiences really are that allows people to concoct all kinds of BS.

Fish could feel the same pain humans do, or could not feel pain at all. We have no way to detect the presence of pain even in humans.

There are human behaviors associated with pain, but we can’t be sure if those behaviors in other creatures are in response to what humans call pain. And some humans show little response to pain while others show a great deal.

It is even possible for other creatures to feel more pain than humans.

Most likely if humans realized just how badly some humans and animals suffer, they would behave much differently. It insensitivity to pain that leads to an absence of empathy, and people not caring about the plight of others.

You tend not to care about people throwing stones, until you find yourself living in a glass house. Then all of a sudden you realize throwing stones is not such a good idea.

We are the homunculus. A tiny part of our brain feels or more precisely creates the non-physical entity we are that feels.

We are hermetically sealed off from the physical universe, but sit comfortably or not so comfortably observing and experiencing a 3-D hologram reality.

It is all very odd and bizarre.

We have to remember all the images we see and experience are in our minds. They may represent an external reality. Or they may not.

If there is an objective, external reality, it is nothing like the one we observe. We wouldn’t recognize ourselves or anyone we knew if we saw them the way they really were—a quantum field we can’t even imagine.

People imagine we know so much about reality, when in truth we know so very little.

Sentience: The capacity to experience feelings and sensations caused by stimulation. Sensations are local to the stimulus, feelings are more general.

If you kick a stone, the stone moves in response according to the laws of physics but, being just insentient matter, it feels nothing. If you kick a dog, the dog, being sentient, will experience the sensation of pain and might also feel upset at the sudden unwanted impact, and is likely to react of its own accord in some way. [*Don’t try this at home.]

Sentience and awareness are slightly different. Awareness is a function of attention: it’s the capacity to perceive what is being experienced beyond the raw sensations.

Also, sentience is not to be confused with sapience (wisdom) or self-awareness — a common mistake in science fiction.

Sentience is a creatures ability to feel emotions. This goes beyond people to animals and, in some Eastern philosophy, all things.

This isn’t to be mistaken for a logical conclusion resulting in hormonal responses. This is more the natural hormonal response we have to what we experience.

ie. I was very angry at my roommate when I came home and he had not mowed the yard (sentient emotion). After calming down I realized that my anger came from expectations I had created for him in my own mind and could no longer blame my anger on him. He’s usually unreliable for chores, so it was foolish of me to expect a different result (logical emotions).

A sentient being is basically any level of conscious aware intelligence. Many of these terms are similar in meaning of closely related.

Being conscious is the act of an intelligence being aware of something and that is the same thing as the act of being sentient.

Being aware is an intelligence which is able to sense and act with it’s intelligence upon that which it senses.

Being intelligent is the ability to sense something, to make decisions based on what was sensed, to learn something from what is sensed and the actions taken, and thus to gain knowledge and skills which can be applied to future decisions. To be intelligent does not require being very intelligent, just the minimal amount required to gain and apply some form of knowledge, however simple. At the simplest most primitive levels a virus is intelligent, sentient, aware, and conscious.

Now, sapient is different, because to be sapient means to be an intelligence with wisdom.

Self-awareness is also different. An intelligent aware life form does not need to be intelligent enough to understand what self-awareness is.

Because of this, all life is sentient, intelligent, conscious, and aware.

How do you define sentience?

Sentience is an organism that has the capacity for sensation or feeling. A sentient being of mortal existence has the power of perception by the senses and is conscious or has consciousness.

Amoeba has no special sense organs. Changes in the outside world are detected by all parts of the living material. In general, this sensitivity ensures favorable surroundings. For instance, amoeba quickly moves away from very bright light or strongly acidic or alkaline water. This means that an amoeba, one-celled protozoa, that can sense light but is not conscious is therefore also not sentient.

Thanks for A2A.

Rather than resort to a bland dictionary definition, the word sentient has come to mean something greater: “To have an awareness of self-awareness.” I know that seems circular, but just an awareness of surrounding environment is no guarantee that a creature is sentient.

A chimp has incredible intelligence, but will still fight with the other chimp in a mirror. My parents had a cat that used to fight with other cat in the bottom of the toilet! There’s a New Zealand farmer who doesn’t use dogs to round up his sheep. Because sheep have a tendency to flock together, he just uncovers mirrors inside the evening safety pen. The sheep form a new flock with the ones visible in the mirrors.

The larger aquatic mammals, like Dolphins and Porpoises are capable of recognising themselves in a mirror. It’s a reasonable assumption that the Blue Whale and the Orca pass the same test, but the amount of space required to test these animals without harming them is just too great. The elephant passes the mirror test. Even if our only means of communicating with these animals is through treats and/or cruelty* does not detract from the display of sentient behavior.
* Domestication of an elephant begins at a very young age. The simplest example is the chain around the leg. A baby elephant is firmly chained so that it simply cannot get away. By the time it acquiesces to human domination, a simple rope (which an elephant could break with one good tug) is enough to keep it submissive. Ironically circus elephants are treated better than their enslaved counterparts in their native environments. These elephants are put through a “crush” process to make them completely submissive, and when you see an elephant creating a painting, most people are too busy watching the painting process to notice that the elephant’s operator is tugging on the elephant’s ear to guide it into creating what is wanted. Any child or adult who has been through domestic abuse can understand this—the cruelty and the pain result in giving up “free will” and acquiescing to the dominant party.

So, being sufficiently aware to have a sense of I is, in my opinion, adequate proof that a creature is sentient.

Any definition you can come up with will be lacking. And typically, circular.

I see another answer say things like "ability to consciously know" and also use words like "understanding" and "realization," without bothering to make sure we've defined those words. Listing synonyms isn't really all that helpful....and any definition that relies on synonyms is simply circular.

I suppose we all have an intuitive notion of what these words mean, but try putting them to a test: see if you are comfortable applying the words to a man-made machine, like a computer or robot or self-driving car or the like. And if not, why not?

So, can a self-driving car "consciously know" that it is sitting at a stop light, waiting for the light to turn green, and for the intersection to be clear of potential obstacles? Do you define the words "conscious" and "know" such that they can apply to the machine, or not?

If you can't easily answer this question (and remember to consider not only current tech, but imagine a self-driving car of 50 years in the future), you just aren't going to be able to come up with a definition that doesn't just use words that are equally hard to define.

I consider Sentience the ability to have pleasurable or painful sensations, which implies having preferences and interests (avoiding pain, seeking pleasure). There is no doubt that sentience has moral relevance.

I consider Subjectivity (or Consciousness) the ability to experiment. Within experimentation I include the ability to feel pleasure and pain, but I also include having a point of view, being someone, perceiving, having “consciousness”.

When I speak of “pleasure” I refer in general to subjectively positive experiences and with “pain” I refer to subjectively negative experiences.

If someone is sentient, then he is conscious, at least in some way. But not necessarily the other way around. That is to say, someone (a robot, a virus, an atom) could be a subjective, conscious being, but within the type of experiences that it has, it could happen that none were of the pleasure / pain type.

I consider it impossible to have pain without being conscious (in some way) of the pain. If someone feels, then that someone is also (in some way) “conscious”. But I admit the possibility of being “someone” (being subjective) without feeling pleasure / pain (without feeling). That is, I admit the possibility of having consciousness without feeling pleasure / pain.

There are other uses of the word consciousness that refer to relatively high states of lucidity or mental clarity, in which there is a good capacity to recognize, identify, define and express (verbally) with certain precision the mental states that are experienced. That is not the meaning of the word consciousness that I use here. In the definitions that I use, a human child can experience the pleasure and beauty of a landscape without having words to identify colors and objects, without knowing exactly what he is seeing, without understanding it, without thinking about what he is seeing, without thinking about the fact that he exists and that he is doing the action of seeing. A possible solution to avoid this misunderstanding is to use the word Sentience and the word Subjectivity, avoiding the word Consciousness.

To be sentient is to be aware of reality. Scientists discuss and come to broad agreements on how much awareness of which aspects of reality is necessary to qualify an organism to be broadly accepted as sentient. Proposals for considering an organism as sentient are tested by scientists who describe and publish their methodologies and experimental observations.

An organism is considered sentient by most scientists when there is clear evidence that an organism is aware of some significant aspects of reality.

Obviously there are many organisms that barely qualify or do not qualify as sentient and many that nearly all scientists agree are sentient.

Sentience can be understood as knowing and caring, indivisible, and is ascribed to living beings, which both perceive their environment, and themselves in their environment (thus some element of self-awareness), in the context of survival and thrival.

This is particularly true of the buddhist perspective on sentient beings, which are all said to have buddha-nature, bodhicitta. Citta is Sanskrit for mind/heart. Unfortunately there is no similar word in the English language to denote both knowing and caring. More technically, bodhicitta is defined as prajna (noetic capacity), shunyata (emptiness qua openness within which stuff happens), and karuna (compassion).

This is not foreign to western thought. Heidegger, for example, explores how care is the Being of Dasein (human existence).

This is important re the current emphasis on Artificial Intelligence, with intelligence taken to be reasoning and pattern matching: the notion of care is not present. A better research goal would be Artificial Citta, or, even better, Symbiotic Citta. In fact, given that software agencies are more and more autonomous, it seems essential for them to embody caring agency, in close concert with us humans. Sentience then can evolve from organic life forms to also include the tools systems human life forms evolve.

“Think you of the fact that a deaf person cannot hear. Then, what deafness may we not all possess? What senses do we lack that we cannot see and cannot hear another world all around us?” -Paul Muad’Dib

I believe every living organism is sentient in its kinds context (among others of its kind) and to its kinds degree (the level of awareness).

Derived from Latin- “Sentire”, meaning “Feeling”. I think Sentient means self aware- An organism ‘acknowledging’ its own existence relative to others. (“Me vs. Them”) I believe to be a living thing is intrinsically to be self-aware.

By “all life”, I mean ranging from the smallest microorganism, Mycoplasma genitalium, or even a singular blood cell, bacteria, fungal spore; all the way to the blue whale and the giant redwood tree; the only difference being that of degree.

By degree- a random example: I’d imagine a red blood cell would “know” that it is “among” “others”, but it might not “know” that it is part of a human body. A human being’s sentience is to a degree that it can differentiate between Conscious and Subconscious, or between Id, Ego and Superego (subsequently being able to experience higher emotions like ambition, malice, love etc)

I don’t think it’s possible to share perspectives of sentience across different organisms. For example I would imagine that it may be difficult for a human to imagine or describe the life of a cell, moving through blood vessels, without sensory organs or any way (we can tell) to identify the world around it.

A friend of mine was in a coma for a week, later after her recovery she tells me she can remember being vaguely aware of her surroundings, but her previous solid memory was before her accident. I think the coma reduced her level of awareness (perhaps to dull the shock or maybe the energy was put to better use elsewhere in her body).

Certain chemicals like LSD, DMT and Ayahuasca are said heighten sentience albeit temporarily.

I believe there is much more to this universe than meets the eye. Hopefully our species will exist long enough to evolve into higher consciousness, higher planes of awareness to experience more of this fascinating universe.

Sentience is ascribed to an entity who can know that they know. Who can know that they know that they know, etc ad infinitum. Clearly, I cannot really know that you know that you know anything. Only you can. Sentience is clearly subjective, however everyone generally assumes they can infer approximately but generally accurately what another knowingly knows. In those cases, their application of the word in such situations seems justified.

Conciousness is ascribed to an entity who has a distinct sense of self, who knows what he/she has been, what he/she aspires to be, his/her potential, and his/her goals.

A pet dog, for example has a degree of consciousness but whether it knows that it knows where to find its supper is questionable. IMHO beings can be conscious without being sentient.

What are the differences between personality and sentience?