Dispelling common misconceptions about sentience-centered ethics

1. Understanding sentience-centered ethics

To give someone moral consideration means to avoid harming them and to seek their benefit. The criterion of sentience holds that we should give moral consideration to all beings capable of having experiences.

The basic idea is this: for there to be harm or benefit, there must be someone being harmed or benefited, and what makes an individual a someone (rather than a something) is the capacity to have experiences.

Sentience-centered ethics maintains that the well-being of every being capable of suffering or enjoyment is valuable in itself. From this perspective, the fact that an animal would be harmed by a certain course of action is, in itself, a reason to avoid that course of action; and the fact that an animal would be benefited by a certain course of action is, in itself, a reason to pursue it.

Now consider some applications of this perspective:

• Regarding animal exploitation: What is fundamentally wrong with animal exploitation is the harm done to the animals themselves (regardless of its indirect effects on human interests or the environment).
• Regarding the suffering of animals in nature: The suffering of wild animals should be reduced simply because suffering is bad for them (regardless of any indirect effects on ecosystem or species conservation).

Sentience-centered ethics is often misunderstood. In this text, we will discuss some of the most common misconceptions about it.

2. Is the criterion of sentience ultimately anthropocentric?

A common criticism and why it doesn’t hold up

People who defend anthropocentrism (the idea that humans should be the center of moral concern) choose a typically human characteristic, such as our capacity for reasoning, and assign degrees of moral consideration to other animals based on how similar they are to us in that characteristic.

Some critics argue that proponents of the sentience criterion do exactly the same thing: they note that humans are sentient and therefore decide to consider only sentient beings, excluding plants, fungi, and bacteria.¹ According to this criticism, in both cases, what matters is resemblance to humans, the only difference being which characteristic is used as the standard of comparison.

Why is this criticism wrong?

There are two key reasons:

1. There is a fundamental difference between using reasoning ability and using sentience as a moral criterion. Reasoning ability does not determine who can be harmed or benefited. Sentience does as  it is precisely the capacity to be affected positively or negatively.
2. Defenders of the sentience criterion aren’t saying “we should consider sentient beings because they resemble humans.” They’re saying the opposite: “We should consider humans (and other animals) because they are sentient.”

Think about it:

If humans were not sentient i.e if we couldn’t feel pain, pleasure, or have any experience at all; the sentience criterion would still indicate which beings deserve moral consideration. This shows that it’s not about using human characteristics as the standard, but about recognizing a fundamental capacity: the capacity to be affected by what happens. Therefore, it is false to claim that the criterion of sentience is, at its core, anthropocentric.

3. Does the criterion of sentience discriminate against non-animal beings?

Understanding the objection of “kingdom-ism”

The criterion of sentience holds that we should give moral consideration to all beings capable of having experiences, such as feeling suffering and pleasure. Some critics argue that this amounts to a form of discrimination based on biological kingdoms, because it includes members of the animal kingdom and excludes members of other kingdoms, such as plants and fungi.

Why this objection fails

Defenders of the sentience criterion don’t say: “We should consider sentient beings because that’s a characteristic of the animal kingdom.” They say: “We should consider most animals we know because they are sentient and can therefore be harmed or benefited.”

Important facts:

• Not all animals are sentient: There are animals that very likely aren’t sentient because they lack a nervous system, or don’t have one sufficiently organized.² Examples include sponges and jellyfish. The sentience criterion doesn’t advocate moral consideration for these animals.
• If other beings were sentient, they’d be included: If it were ever discovered that a plant or fungus is sentient, the sentience criterion would include them within the sphere of moral consideration. So far, however, there’s no solid evidence of that.
• The criterion extends beyond the animal kingdom: In the future, if sentient robots, sentient machines, or sentient digital beings come to exist, the sentience criterion would include them as well.³

Conclusion: The accusation of “kingdom-ism” doesn’t hold. The sentience criterion is different from the criterion of “belonging to the animal kingdom.” According to the criterion of sentience, what matters is the capacity to have experiences, not biological classification.

4. According to the criterion of sentience, is suffering the only problem?

A very common misunderstanding

Sentience is the capacity to have experiences. It is what distinguishes individuals from things:

• Sentient beings are someone
• Non-sentient things are something

Sentient beings are not just living bodies; they are individuals who can be affected positively or negatively. There is someone “inhabiting” those bodies.

The mistaken criticism

Some people say, “If the criterion of sentience were correct, all moral problems could be solved with painkillers and anesthesia.” Since there are ways to harm someone without causing suffering (for example, painless death, or winning a prize and not being told about it), they conclude that there must be something wrong with the criterion of sentience.

Why this argument is wrong

The mistake lies in assuming that considering sentient beings means only caring about their suffering. This is false.

What the criterion of sentience actually recognizes

A sentient being can be harmed in two ways:

• By the presence of what is harmful
• By the absence of what is beneficial

The two examples mentioned by the criticism (painless death and not being told of a prize) are fully acknowledged by the sentience criterion. In fact, the best way to explain these harms is through sentience itself: they are harms caused by the absence of positive experiences.⁴

Think of it this way:

To understand why death or not being told of a prize are harmful events, we need to imagine what the individual would experience in each situation and assess which one they would be better off in. That already presupposes the importance of sentience.

Important conclusion: It is false that the criterion of sentience fails to recognize harms that occur without suffering. Avoiding suffering is a crucial part of caring for sentient beings, but it is not the only concern.

5. If sentience is what matters, why are there harms that do not affect experiences?

A challenging example:

Imagine someone is assaulted while unconscious and never learns about the abuse. Imagine also that the abuse causes no negative experiences in the future and does not reduce the person’s positive experiences. In this case, the abuse does not change the amount of negative or positive experience the victim has.

Some argue that this example shows a problem with the sentience criterion.

But does it really? Distinguishing two different debates:

Debate 1: What should be the criterion for moral consideration? (In other words, which kinds of entities should we consider morally?) The sentience criterion answers this question.

Debate 2: In what ways can sentient beings be harmed or benefited? This question is addressed by theories of well-being.⁵

The key point

Those who accept the sentience criterion can recognize that sentient beings can be harmed:

• By negative experiences
• By being prevented from having positive experiences
• Possibly in other ways as well (such as having their preferences disrespected)

The sentience criterion only tells us which beings we should consider. It does not specify all the ways those beings can be harmed.

In the example of someone assaulted while unconscious, there is still harm to a sentient being (if it were an object, there would be no harm at all). This harm could be explained, for instance, by the violation of the person’s preferences (the preferences they actually have, or those they would have if they had the relevant information).⁶ And preferences depend on sentience to exist.

Conclusion: This kind of example may be an objection to the hedonistic theory of well-being (which says that only experiences matter), but it is not an objection to the sentience criterion. They are two different debates.

6. Does the criterion of sentience exclude insects?

Addressing an important concern

Sometimes people say: “If we must give moral consideration to insects, then we should reject the criterion of sentience and adopt the criterion of biological life.”⁷

Why this criticism fails

First, let us clarify something about sentience: it is not only about feeling pain. Sentience is about having any kind of experience, whether positive or negative.

Even if insects could only have positive experiences (from smelling, hearing, tasting) and did not feel pain, they would still be sentient. The criterion of sentience would include them, because it also recognizes harm caused by the deprivation of positive experiences.

What if there is doubt about whether insects are sentient?

Any responsible moral theory prescribes giving the benefit of the doubt where there is reasonable uncertainty. Why?

If insects are not sentient and we treat them as if they were, the cost to us is small. But if they are sentient and we treat them as if they were not, the harm to them is enormous.

Conclusions: We should treat insects as sentient beings until proven otherwise. The burden of proof lies with those who deny their sentience, not with those who recognize it.

The numbers are staggering:

There are about 10 quintillion insects in the world.⁸ Even if only 0.01% of them were sentient, that would still amount to 100 quadrillion individuals. Moreover, there are strong reasons to believe that the percentage of sentient insects is not small.

A fundamental question:

Suppose no insect were sentient. Why should we care about them if there were no one inside those bodies, and whatever happened to them would make no difference to them? The intuition that insects deserve moral consideration seems to come precisely from the possibility that they are sentient. And there is good evidence that many of them, in fact, are.⁹

7. Does accepting the criterion of sentience mean assuming that values are subjective?

Understanding a common confusion

The criterion of sentience says that the beings for whom things can go better or worse are sentient beings, that is, beings that have subjectivity.

The objection

Some say: “If we accept that the existence of beings with subjectivity is necessary for a situation to be better or worse, we are assuming a subjective conception of value. That would mean that there is nothing objectively good or bad that everyone should recognize.”

But this objection confuses two different meanings of the word “subjective.”

Two meanings of ‘subjective’:

1. Something can be subjective in the sense of referring to consciousness (the capacity to have experiences).
2. Something can be subjective in the sense that there is no objective truth about it.

One does not necessarily imply the other.

How this works in practice

It is possible to defend that happiness has objective value in itself and that suffering has objective disvalue in itself. According to this view:

• Sentient beings merely recognize what has value or disvalue
• They do not create that value or disvalue
• The value of pleasure and the disvalue of suffering come from their intrinsic characteristics

Think about it:

Defending that some things are objectively good or bad does not mean having to say that species, ecosystems, or non-sentient life have intrinsic value. It is perfectly consistent to claim that:

• There are things that are objectively good or bad
• For value or disvalue to exist, there must be beings for whom things can be positive or negative

Conclusion: The objection confuses two meanings of the term “subjective.” Accepting the criterion of sentience does not necessarily mean assuming that values are subjective in the sense of denying objective moral truth.

8. If there is a need for environmental ethics, does that mean the criterion of sentience is wrong?

A common argument and why it fails

There is an argument that says: “If there is a need to develop an environmental ethic (principles to guide decisions about the environment), and if environmental ethics questions make sense, then ecosystems and species must have intrinsic value, not just value as resources for sentient beings.”¹⁰

The problem with this argument

The need to develop an environmental ethic does not imply that non-sentient entities have intrinsic value. Part of the confusion comes from the fact that the term environmental ethics is used in two different senses:

1. Environmentalism: the view that certain non-sentient entities, such as species and ecosystems, have intrinsic value.
2. The field of practical ethics that deals with the morality of our actions affecting the environment.

One of the central questions of this field is precisely: “Do non-sentient entities have intrinsic value, or only value as resources for sentient beings?”

An important point about asking questions

That a question makes sense does not mean the answer must be “yes.” For example:

• “Is there life on Mars?” It makes sense to ask, but the answer might be “no.”
• “Did Brazil win the 2014 World Cup?” It makes sense to ask, but the answer is certainly “no.”
• “Do species and ecosystems have intrinsic value?” It makes sense to ask, but the answer could be “no.”

Another example that helps illustrate this

It is also necessary to develop an ethics of income distribution, but that does not mean that income distribution itself has intrinsic value. The issue matters because it affects individuals’ well-being.

Similarly, there may be a need for environmental ethics precisely because sentient beings are indirectly affected by how we impact their environments.

The problem with certain labels

Sometimes it is claimed that only environmentalism counts as a “true environmental ethic,” while viewing the environment as a resource for sentient beings is merely a “resource management ethic.”

But using those labels does not constitute an argument
It simply assumes in advance that environmentalism is correct, which is precisely what is at issue and must be demonstrated. This makes the reasoning circular, and sometimes it is used as a rhetorical strategy.

Open questions

It may turn out that the most appropriate approach to environmental issues involves rejecting “genuine environmental ethics” and accepting some form of “environmental management ethics,” such as preserving or modifying the environment in ways that are best for sentient beings.

Conclusion: The argument from the need for environmental ethics is circular and does not show that the criterion of sentience is inadequate.

9. If being alive is necessary for sentience, does being alive have intrinsic value?

A common argument

It is sometimes argued that since an organism must be alive to be sentient, we should give moral consideration to all living beings, sentient or not.

The flaw in this argument

Even if biological life is necessary for sentience, this does not justify giving moral consideration to non-sentient living beings. Why?

Because it only shows that biological life has instrumental value, as a means for sentience, not intrinsic value.

Understanding the difference

Showing that something has value as a means does not show that it has value in itself.

For example:

• A pencil has value as a means to write.
• But that does not mean the pencil has value in itself.

Similarly:

• Biological life has value as a means to sentience.
• But that does not show it has value in itself.

Conclusion: Even though this observation gives us reasons to keep sentient beings alive, it does not give us reasons to preserve non-sentient organisms.

10. Is sentience only a means to preserve life?

The opposite argument

Another argument tries to claim that what has intrinsic value is biological life, not sentience.

It points out that:

• Sentient beings use pain to avoid what would kill them.
• They use pleasant sensations to identify what helps them stay alive.

According to this argument, sentience is merely a means to preserve life. Positive experiences would not have intrinsic value, and negative ones would not be bad in themselves. The value of sentience would be merely instrumental to what truly matters, being alive.

Why this argument is wrong

The main problem is that from the fact that sentient beings strive to stay alive, it does not follow that they regard biological life as having intrinsic value.

Think about it:

• The main reason we avoid negative experiences is the fact that they are negative.
• Of course, we may also avoid something that causes suffering because we know it would kill us.
• But from the fact that we want to stay alive, it does not follow that we see biological life as having value in itself.

How we actually think about being alive

We usually think that being alive is good because it allows us to have valuable experiences. Sentient beings pursue certain things because they value the experiences those things provide. They do not see those experiences as having value merely as tools for staying alive. On the contrary, being alive is good because it allows such experiences.

If those experiences also help us remain biologically alive or sustain our species, that is only a side effect. By itself, that does not show that sentient beings pursue those things as ends in themselves.

A test of our intuition

We normally think that life is worth living when it contains enough valuable experiences to make staying alive better than dying.

If we believed that biological life had value in itself, we would have to accept that there is something good about:

• Remaining as a living body with no possibility of ever having experiences again, or
• Experiencing only extreme suffering and nothing else.

But that does not seem to be the case.

Conclusion: We have reasons to conclude the opposite of what the objection claims. Being alive has value only as a means to having meaningful experiences.

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Notes