Consider two things you have almost certainly done. At some point recently you killed a small animal — a mosquito on your arm, a fly at the window — without pausing and without feeling anything, and you would think it odd to have felt anything. And somewhere in your life there is an animal you would never harm: a dog, say, that you would not hurt for any amount of money, whose suffering would sicken you, and which you grieved, at least a little, when it died.
Notice how you told those two apart. You did not consult a chart of species. The mosquito is not human; the dog is not human either. You were applying a different test, and you applied it so quickly and so surely that you never noticed doing it. The test is roughly this: is there anyone in there? Is there a someone — a being for whom things can go well or badly, a life that can be lived well or badly by the one living it — or is this simply a small mechanism with legs? The mosquito failed that test. The dog passed it. You sorted them by what was present inside each, not by the label each wore, and you were so certain of the result that you never felt yourself decide.
That test — judge a being by the capacities it actually has, not by the kind it belongs to — is one of the criteria we trust most completely in all of morality. And there is something we rarely notice about how we use it. We apply it downward, to the animals beneath us, where the answers come back easily and cost us nothing. Tonight we follow a philosopher who refuses to stop there. He takes the same test and applies it upward — through the dog, through the ape, and then, without stopping, into the margins of human life we usually keep it away from. And it keeps returning clear answers. They are simply not answers we can easily live with.
This is Philosophy for Us — philosophy for everyone, no degree required.
This is the third of eight episodes on who counts as a full person, and who decides. Last time we found where the familiar picture came from — the full person as the rational, self-aware adult. That picture is not bedrock. It was assembled around 1689, and built for the courtroom, to carry blame across time. Tonight we stop handling it carefully. There are careful, consistent philosophers, alive now, who take that made criterion, decline to flinch, and follow it exactly where most of us do not want it to go: to the conclusion that some human beings are not, in the full and weighty sense, persons, and that a great ape may have the stronger claim. That is the conclusion most listeners will most want to reject. Tonight I want to state it at its full strength. And I will say now what to brace for: the difficulty is not that this view is monstrous and foreign. The difficulty is that it is built out of principles you already hold.
Let us begin at the bottom of the scale, where the reasoning is easy and where you will agree with every step. It is worth beginning there precisely because you agree — the agreement is the point, and it will matter later.
Start with the philosopher Peter Singer, and with the premise on which he builds everything. In his book Practical Ethics, Singer's starting point is almost plain to the point of being dull. Of any being, ask one question: is there anyone home? Not is it clever, not is it like us — is there a someone there, a being for whom things can go well or badly? Can it suffer? Does it have interests of its own, a stake in how its life goes? If the answer is yes, then those interests count. And — this is the decisive part, so I will go slowly — they count equally. A pain is a pain. Like interests carry like weight, whatever body they happen to occupy. Singer calls this the principle of equal consideration of interests, and that is all it is: if a being can be hurt, its being hurt matters, and it matters just as much as anyone else's being hurt to the same degree.
We already live by this principle; we simply never name it. Consider honestly why we do not grieve a clam. You eat one without a flicker; you would not hold a funeral. Why not? The reason is not that the clam is not human — it cannot be, because the dog you would grieve is not human either, and we treat the two entirely differently. The honest reason is the question from a moment ago, the one we run without hearing it: is there anyone in there? And as far as anyone can tell, in the clam there is almost no one — no nervous system to speak of, no one for whom the world appears, nothing it is like to be a clam, no life that can be set back because there is no one there to set back. The clam fails the test. The dog passes it easily. We decided that by capacity, not by kind, and we were so sure of the verdict that we never noticed reaching it.
Here is where that plain-looking premise does far more work than it appears to. Singer did not build it to settle debates about the hard margins of human life. He built it as an argument against eating meat. Follow one step with him. If a pig has interests — and it plainly does; there is unmistakably someone there, who can suffer, who minds, who would rather not be where it is — then the pig's suffering counts. And by equal consideration it counts as much as ours would, where the interests are alike. A like pain, a like weight. Which means the factory farm is not a regrettable cost of doing business. On this premise it is a moral catastrophe on an industrial scale, and the whole of it rests on a single assumption: that those creatures do not count the way we count. That is what the premise is for. It was never mainly a puzzle about apes and grandmothers. It is an argument that ordinary, decent people are, at this moment, paying for something monstrous, and have licensed it with one unexamined assumption — that the sufferers are the wrong kind, so their suffering can be rounded down toward nothing. Whatever one finally thinks of Singer, this part is hard to escape once the premise is granted — and we granted it the moment we spared the dog.
Now one distinction has to be held firmly, because the rest of the episode depends on not letting it collapse. Everything so far has concerned suffering — whose pain goes on the scale. The premise tells us that hurting the pig is wrong, that the clam's near-absence is why we owe it almost nothing, that cruelty is cruelty whatever the species. What the premise does not tell us, at least not by itself, is what is wrong with killing. Not hurting — killing: taking a being we never cause to suffer at all, and ending it gently, painlessly, in its sleep. On the question of killing the premise falls silent, because no interest in avoiding pain has been crossed. And that silence is exactly the gap into which the word person returns — the made thing from last week, taken up again and put to a far more demanding use.
So what exactly is wrong with killing? Set aside the easy answer, which is the suffering, because we have just seen that suffering cannot be doing the work — one can kill without causing a moment of pain. Singer takes this seriously, more seriously than most people are willing to, and the step he takes turns the question from one about cruelty into one about us.
Take a being that can suffer but has no sense of itself across time — no picture of its own tomorrow, nothing it looks forward to or dreads, no project it experiences as its own and ongoing. A fish, on Singer's account, is roughly like this. Hurt it and you have done something wrong; its pain is on the scale, that holds. But kill it gently, in its sleep, and it becomes genuinely difficult to say whom you have wronged. The being that existed had no stake in a future, because it had no capacity to hold one. There was someone there who could feel. There was not someone there who was going anywhere.
Now take a being that can hold its own future in mind — that knows, dimly or sharply, that it exists across time, that there is a tomorrow belonging to it, things it is reaching toward, a life it experiences as its own unfinished undertaking. Kill that being and you have taken something the fish never had to lose: a future it was already living into, a continuation in which it had a stake. That, Singer says, is the special wrong of killing — not the pain, but the removal of a future from a being that could hold one. And the name for a being with that capacity — self-aware, aware of itself as persisting through time — is a person.
We have met this person before, last week in fact. This is Locke's forensic person, taken up again and put to a new use. Recall what we found: in his Essay Concerning Human Understanding of 1689, Locke rebuilt "person" around self-consciousness — "a thinking intelligent being that can consider itself as itself, the same thinking thing, in different times and places" — and he built it for the courtroom, to ensure that the man in the dock is the same person who did the deed, so that blame falls on the right one. Watch what Singer does with that same tool. He takes the very same category — a self that holds itself together across time — and moves it from one task to another: from settling whom we may blame to settling what makes a death a tragedy. The same criterion; a different courtroom. The concept we were told last week had a date of birth and a job is now being used to decide who may be killed.
And Singer is not alone in reaching this conclusion — but the philosopher who joins him gets there by a different argument, and the difference matters, because careless versions run the two together. Jeff McMahan, in his book The Ethics of Killing, published in 2002, reaches a closely related conclusion without leaning on the word "person" at all. His central device he calls a time-relative interest. The idea is this. How bad is a death — how great a misfortune is it — for the one who dies? It depends, McMahan says, on how much that being loses, weighted by how psychologically connected it was, at the time, to the future the death removes. A being richly bound to its own tomorrow — plans laid, relationships under way, a self extending continuously into that future — loses enormously in dying, because so much was tied to the future now cut off. A being barely connected to its own future — a newborn, with no projects, no sense of a life in progress, only the faintest connection between who it is now and the life that might have followed — loses less, in the precise sense McMahan intends, because so little bridged it and that future. So for McMahan the wrong of killing is not a switch that flips when a being qualifies as a person. It varies by degree. It scales, smoothly, with how much held future is destroyed. Two moralities of killing, he argues: the one governing the killing of beings like us, richly self-aware and bound to our futures, is simply not the one governing the killing of beings only thinly tied to theirs.
Two different accounts, then. Singer's draws a line — person or not — and rests the special wrong of killing on which side of it a being falls. McMahan's refuses the line and offers a gradient instead, the wrong scaling by degree of psychological investment. I am keeping them apart deliberately, because they are not the same argument and each deserves to be met on its own terms. But now notice what they share. Both make the wrong of killing depend on a psychological capacity — the holding of one's own future — that some humans have richly, that some humans have barely or not at all, and that some animals have more of than some humans do. And neither will allow "but it is a human being" to settle the question. That refusal — the refusal to let bare species membership do the work — is not an accident of the theories. It is a principle. And it is a principle we hold too. That is where we turn next.
A single principle has been running underneath both accounts, and once it is named it will be recognisable as one you already hold — because you already use it, though only ever against other people's prejudices.
It has a name. The philosopher James Rachels built much of a book, Created from Animals, published in 1990, around it, and called it moral individualism. It holds this: to know how to treat a being, look at that being — its actual properties, what it can really do, feel, suffer, and want — and never let the group it belongs to stand in for the individual in front of you. Judge the one, not the kind. And we do not merely believe this; it is the entire moral content of our opposition to racism and to sexism. Ask why it is wrong to pay a woman less, or to trust a man less, or to grant and withhold on the basis of skin colour. Stripped down, the answer is always the same: because one is reading the individual off a group label instead of looking at the person, letting the category decide what only the actual person in front of one should decide. We hold this deeply. Don't tell me what they are; show me who they are — that is not a slogan to us, it is close to bedrock.
Now watch Singer turn it around. He takes the principle we hold and asks why we have carved out exactly one exception to it. We judge the individual and not the group — except, he observes, in one place. When the group is the species, we stop. There, and only there, we let bare membership do the whole job: it is a human being, and full standing is granted at once, with no examination, no looking, no asking what is actually present inside. Singer has a name for that surviving exception, and he built it to sit alongside the prejudices we have already abandoned: speciesism. He did not coin the word — a writer named Richard Ryder coined it, around 1970 — but Singer is the one who drove it into common use, and he aimed it directly at us. The charge is precise. We gave up "because they are our kind" as a reason everywhere it cost us something to keep it — across races, across sexes. We retained it in exactly one place: the one place where giving it up would force us to change how we live. And in that one place we have never actually offered an argument. We simply helped ourselves to the exception and hoped no one would check.
Here is where the argument has its consequences, and they run in two directions, and I am going to state both plainly, because the whole point of the episode is that neither can be softened into something we are permitted to wave away.
Apply the criterion upward, honestly, and it says this. The great ape who plans several steps ahead, who grieves, who knows herself across time — she has the capacities the argument holds to matter. They are genuinely present; the criterion registers them and is indifferent to her species. So she may have a stronger claim on the protections we reserve for persons than we have ever been willing to grant her. And we do not get to set the criterion aside because she is the wrong kind — because setting it aside on grounds of kind is precisely what we have spent our moral lives condemning in everyone else.
Apply it downward, and this is the harder direction. There are human beings in whom these capacities are not present and never will be. Singer and McMahan do not look away from naming them, and I will not either. A newborn with anencephaly — born without the upper brain, without the parts that could ever make experience or a self possible, with no prospect of a future it could hold. A person in the last extremity of dementia, past the point where anyone is looking out at all. If the special weight — the personhood that makes killing the special wrong — is built out of holding one's own future in mind, then these human beings do not have it, and so they are not, in that weighty sense, persons. And the ape may have the stronger claim. Bare humanity, on this view, is simply not what conferred the standing. It was a prejudice no one had ever challenged.
Now stop and see clearly what this is, and, more importantly, what it is not. It is not cruelty. This is not a man who hates disabled people, or wants anyone's grandmother dead, or feels nothing. It is very nearly the opposite of feeling nothing. It is what results when someone takes the principle we hold — judge the individual, never the group — and refuses, on pain of plain inconsistency, to grant himself and his own kind the one exception the rest of us quietly grant ourselves. Singer and McMahan are not cruel. They are the most consistent people in the debate. They looked for the single place where we cheat — the one group we wave through on a label without ever checking what is inside — and they declined to cheat there too. Every conclusion that appals us is the consequence of a principle we would not surrender if asked to. That is why it has the force it does: not because it is foreign to us, but because it is ours, followed all the way down by someone with the nerve not to flinch at the bottom.
So consider the position we are now in, because it has fewer exits than it first appears, and each closed exit is one we closed ourselves.
You came in wanting to reject this view — of course you did; it ends somewhere you cannot bear. So try to reject it, now, and notice what the attempt actually comes to.
You might say: capacities do not determine standing; being human does, and that is the end of it. But that is the charge of speciesism returning, and the difficulty is that you do not actually believe it, and I can show you. You do not grieve the clam and you do grieve the dog, and neither is human. You have been sorting by what is present inside, not by species, your whole life, at the bottom of the scale — and you were right to. So to reject the view by that route, you would have to discard the very judgment that tells you the clam does not matter and the dog does. And you will not discard it. It runs too deep; it is most of your decency.
Or you might say: very well, capacities — but not those ones; some other capacity draws the line. Perhaps. But notice that you are now standing inside the view, not outside it. You have conceded that capacities draw the line; you are now only disputing which capacities, and where. That is a real argument, and we will have it — but it does not free you from the difficulty. It only changes which version of the difficulty you face.
That is the position. We are holding a criterion that is honest, that is consistent, and that we already use — and we have no principled way out of where it leads. Not yet. We are left either to own conclusions we came in to reject, or to reach for an exit that, so far, is not there.
Now hear carefully what I am not saying, because this is exactly the point at which a programme like this one could deceive you, and I will not. I am not telling you the view is right. I have made it strong because it is strong — honest, consistent, hard to answer — but strong is not the same as proven, and nothing has been proven tonight, and I will not let one side prevail merely because it argued without flinching. It came in honest. It did not come in true. There are real replies ahead — not consolations, replies — and there are serious people who have spent their lives on precisely this, and who hold that for all its consistency the view gets something fundamental wrong. The question is not closed. I have set out a position with no easy answer, and "no easy answer" is not a verdict. Do not let it win tonight by default, and do not let me hand it the win.
Notice, too, what remains untouched. We have not settled what a person essentially is — the deep question from the first episode sits exactly where we left it, wide open. This argument never needed to settle it. It is not a claim about the deep nature of persons at all; it is a claim about whose life carries the full weight, built from start to finish out of capacities one can point to and measure. The metaphysical question can remain unanswered indefinitely, and the criterion goes on working regardless. That was the division we drew on the first night, and it is why tonight's conclusion holds without waiting on anything deeper.
So here is where we stand, at the third of eight episodes. You came in holding the conclusion you most wanted to reject at arm's length, as though it were someone else's monstrous idea, to be shouted down. You leave having found it assembled out of your own commitments. The criterion that says some humans are not persons and some animals may be is not an intruder you can shut out. It is the criterion you trust most, in the hands of people too consistent to stop applying it where you stop. That is what you take away, and it is a hard thing to accept: you can no longer dismiss this out of hand. You went looking for a monster and found a principle of your own.
And next time you will do what people do here: look for a reply that defeats the view. There are two, and you can already feel yourself considering them. The first is the warmer one — everyone counts; every human being is a full person, and how dare we even ask. The second is the cooler one — the choice was false from the start; standing was never all-or-nothing, it comes in degrees, on a gradient, so the cruel either/or simply dissolves. Two replies. And here is the only thing I will promise about them tonight: both have serious people behind them. They are not slogans; they are positions with real arguments, and next time I will give each the fullest hearing I can. The single open question is whether, at full strength, either reply actually answers the argument we are now facing — or whether it only feels as though it does. I will not settle that for you tonight by announcing the answer. We settle it next time the honest way: by taking each reply at full weight and seeing what is genuinely on the other side.
Before then, one thing to carry, and it is yours to do; I will not do it for you. Find the exemption. Somewhere in you there is a line that says: this being gets the full weight, no examination, no questions — because it is human. Perhaps it is the newborn. Perhaps it is someone in your own family the wider world has quietly written off. Choose the one where you most want to reject everything said tonight and simply declare it: this one counts, and that is the end of it, because they are one of us. Good. Now do the harder thing. Try to say why — and you may not use the word "human," and you may not use "one of us," because that is precisely the exemption under trial. State the actual property, the capacity in them, that earns the full weight. Then turn and check whether the ape has that property too, and decide honestly whether you will now admit her, or whether you have just caught yourself doing the one thing you swore you never would: judging the individual by the group. I am not going to tell you what you will find. I am telling you that the means of deciding is in your hands. It always was. And tonight you lost the right to pretend you do not know how to use it.
This is the third of eight. Stay with me.
Thanks for listening. I'll see you next time.