Funny, innit. An ordinary folk looks out, is perfectly convinced he sees a tree, but you the metaphysician tell him, nahhhh, you don’t. You see a thing, and that thing is only called a tree because somebody, somewhere, some long time ago, said so, and you’re just regurtitatin’ what’s been taught to you.

But then, there’s markedly more ordinary folk than there are metaphysicians, so…..there ya go. “I see a tree” rules the day. — Mww

A relevant passage from here:

Here is a kind of puzzle or paradox that several philosophers have stressed. On the one hand, existence questions seem hard. The philosophical question of whether there are abstract entities does not seem to admit of an easy or trivial answer. At the same time, there seem to be trivial arguments settling questions like this in the affirmative. Consider for instance the arguments, “2+2=4. So there is a number which, when added to 2, yields 4. This something is a number. So there are numbers”, and “Fido is a dog. So Fido has the property of being a dog. So there are properties.” How should one resolve this paradox? One response is: adopt fictionalism. The idea would be that in the philosophy room we do not speak fictionally, but ordinarily we do. So in the philosophy room, the question of the existence of abstract entities is hard; outside it, the question is easy. When, ordinarily, a speaker utters a sentence that semantically expresses a proposition that entails that there are numbers, what she says is accurate so long as according to the relevant fiction, there are numbers. But when she utters the same sentence in the philosophy room, she speaks literally and then what she asserts is something highly non-trivial.

You’re making nouns out of my adjectives. I don’t believe wrongness and rightness and rights are measurable properties of anything. — NOS4A2

So you claim that killing foetuses is wrong but don't need to point to some measurable property of being wrong because "wrong" is an adjective, and others claim that foetuses aren't people and need to point to some measurable property of being a person because "person" is a noun?

Such an argument from grammar is special pleading.

There needs to be some basis for granting rights in the first place. — NOS4A2

That doesn't really address the question. According to your own account of rights there's nothing more to rights than someone having said something like "so-and-so has the right to such-and-such".

So John says "foetuses have a right to life" and Jane says "foetuses don't have a right to life". Where do we go from here?

Do you want to argue that one of John and Jane is correct and the other incorrect? Then there's more to rights than someone having said something like "so-and-so has the right to such-and-such". And so, using your own reasoning, one must be able to point to some measurable property which is "the right" (independent of what either John or Jane say). Can you do that?

But then you also say above that it's not about rights but about wrongness and deservingness, which just shifts the problem: using your own reasoning, one must be able to point to some measurable property which is "wrongness" and "deservingness". Can you do that?

Or perhaps you simply need to accept that not everything is a measurable property that can be pointed to, whether that be "right", "deservingness", or "personhood".

I wasn’t necessarily speaking about rights. I was saying they deserve a chance to live and that it is wrong to kill them. — NOS4A2

I mean you said this:

Our bodies have largely evolved for the task of protecting human life in its earliest development, and many of us hold to right-to-life principles, for instance that a human being in its earliest development deserves a chance to live.

So forgive me for being confused.

Are you now suggesting that it can be wrong to kill a foetus and that a foetus deserves the chance to live even if they haven't been granted the right to live?

"Life begins at conception" is an imprecise short-hand for "a human life begins at conception". Stop picking the low hanging fruits: obviously a sperm is alive and so is my skin cells---we are talking about when a human being is alive. — Bob Ross

I was just explaining what Echarmion was saying. I understood you as misinterpreting him as saying that life begins after conception. Maybe I misunderstood you.

Einstein? The more you post the more evangelistic your approach becomes. This is a site for philosophical argument. Evangelism is literally against the rules. — Leontiskos

My claim is that the scientific evidence shows that naive realism is wrong, and I support this claim by referring to experts in the field, such as Einstein, who best know what the scientific evidence shows.

Are you claiming that Einstein and I are wrong in claiming that the scientific evidence shows that naive realism is wrong, or are you claiming that the scientific evidence itself is wrong?

??? . I can't tell if you are joking. — Bob Ross

I'm not. A sperm cell is a single-celled organism. It's alive.

It is an undisputed scientific fact that life begins at conception: it is the clear beginning mark of the ever-continual development cycle of an individual human being (until death). — Bob Ross

I believe the point he was making is that sperm cells are alive, and so that life began before conception.

Human beings have no rights other than those that have been declared and conferred by others. — NOS4A2

So a foetus doesn’t have a right to live unless some authority declares and confers that right?

Then what exactly are you trying to argue here? Because with the above in mind all we can do is describe the fact that in some places and at some times abortion is legal and in other places and at other times it is illegal.

No measurable property called “personhood” appears or disappears in any given human being — NOS4A2

Most of us are quite capable of understanding what “person” means, that rocks, embryos, and flies are not people, and that adult humans (and intelligent aliens) are people. The type of “personhood” that you think doesn’t exist isn’t the type of personhood that any of us are talking about.

So what grounds are there to make the distinction now? — NOS4A2

The very real and obvious observable differences between rocks, embryos, and flies on the one hand and born humans on the other hand.

The fact that an embryo has roughly the same DNA as me and will eventually grow into an organism like me simply isn’t sufficient grounds to grant it the same rights as me or even just the right to live at the expense of the rights of the woman who must carry it to term.

That’s one of their manifestations, sure. Grab any bill of rights and point to a right, you’ll have your answer in what it consists of. If there is more to it, go ahead and reveal it. — NOS4A2

That's not a right. That's a supposed description of a right. The words are not the thing they describe. I'm not asking you to point to words that describe a right; I'm asking you to point to a right.

As it stands it amounts to me pointing to the word "person" and saying that I'm pointing to a person.

It’s wrong to kill a fetus for the same reason it is wrong to murder a 40 year old. Both are deprived of a future against their will. Both have their bodies destroyed against their will. The world and the community are deprived of their presence against their will. In any case, any evidence or reasoning to support the claim that it is wrong to kill a 40 year old can be applied to any other human being in any other stage of its life, including early development. — NOS4A2

Killing a 40 year old isn't wrong just because "he is deprived of a future against his will". It's wrong because "he is deprived of a future against his will and is a person". The "and he is a person" has moral relevance. It is not wrong to deprive a foetus of its future against its will because a) it's not a person, and b) it doesn't even have a will.

Can I grow fetuses in order to harvest their organs and sell them, in your view? Why or why not? — NOS4A2

You mean like scientists growing ‘mini-organs’ from cells shed by foetuses or cultivating embryonic stem cells in general?

Yes, that's acceptable. It could save many lives.

Relevant paper on that last point:

Could Artificial Wombs End the Abortion Debate?

One should distinguish two aspects of abortion that are currently but not necessarily linked—extraction and termination. Abortion rights might be understood as the right not to be pregnant, the right not to have the human fetus in the womb, the right of extraction. On the other hand, abortion rights might be defined as the right to end the life of the human fetus in utero, the right to terminate not just the pregnancy, but also the life of the fetus. These two understandings of abortion, although distinct, are at least for the present linked, since one cannot currently accomplish evacuation of the human fetus from the uterus at an early stage of pregnancy without also terminating the life of the human fetus. Accordingly, one could advocate the right of evacuation or extraction, that is, the right to have the fetus removed from the woman’s body, and yet not advocate a right of termination, that is, the right to have the fetus killed within the woman’s body.

You can point to a right if you write it down. — NOS4A2

So a right is a piece of paper with ink markings? That doesn't seem right.

To do so to a fetus would deprive it of the chance to ever do so. — NOS4A2

And that's the point of departure. It is argued that it is not wrong to deprive a foetus (or embryo) of the chance to become a person; or that there is insufficient evidence or reasoning to support the claim that it is wrong; or that it is more wrong to force a woman to carry the foetus (or embryo) to term.

Perhaps abortion would be wrong if embryos and foetuses were grown in some artificial womb, but the fact that they grow inside a person with rights of their own is a fact that has moral relevance.

@NOS4A2

I should add that I'm also somewhat perplexed by your questioning of personhood but your acceptance of rights. Can you point to rights? If not then why expect someone to be able to point to personhood as if not being able to is a gotcha?

Some things just can't be pointed to.

I understand, and have no problem with either term in common usage, but if I were to ask you to point to whatever it is you're referring to you would invariably point to your body, which has existed and grown since conception. That's what I'm hung up on. — NOS4A2

Think of the difference between a wave and still water. All waves are water but not all water is a wave. The body (specifically the brain) has to be doing something for there to be a person. If the brain isn't doing that thing then there is no person, which is why neither a corpse nor an embryo is a person.

But one of the challenges the pro-choice advocate faces is explaining the dividing line between killable and not-killable. When and how does that transition take place? — frank

It's gradual.

Let's take the pro-life argument I offered at the start:

P1. It is wrong to kill a baby the day after birth.

The argument would then be:

P2. If it is wrong to kill a baby the day after birth then it is wrong to kill a baby the day before birth.
C1. Therefore, it is wrong to kill a baby the day before birth.
P3. If it is wrong to kill a baby the day before birth then it is wrong to kill a baby two days before birth.
C2. Therefore, it is wrong to kill a baby two days before birth.
...
etc.

This line of reasoning will entail the conclusion that it is wrong to kill a baby from the moment of conception. — Michael

The counter argument is:

P1. It is wrong to kill a baby the day after birth.
P2. It is slightly less wrong to kill a baby the day before birth than the day after birth.
P3. It is slightly less wrong to kill a baby two days before birth than the day before birth.
P4. It is slightly less wrong to kill a baby three days before birth than two days before birth.
...

At some point any degree of wrongness, if there is indeed any wrongness left, is insignificant compared to the wrongness of not allowing a woman to terminate her pregnancy.

It's much like the Sorites paradox. We might not be able to determine where the line is drawn, and there might not even be a precise point where some line is drawn, but we can say at the one extreme a single grain of sand is not a heap and a newly conceived embryo does not have an overriding right to life, and at the other extreme 1,000,000 grains of sand is a heap and a three year old child does have an overriding right to life.

All of them involve the intentional killing of very young and helpless human beings. That’s all I mean. — NOS4A2

But not all of them involve killing an embryo or foetus. That is a significant moral difference.

Abortion rights is often posited as a mark of an enlightened society, when in fact infanticide, child sacrifice, and acts of these sorts is a stone age and barbaric practice. — NOS4A2

Abortion is nothing like infanticide or child sacrifice.

And of course this tired claim has been shown to be unsupportable any number of times in the recent thread — Leontiskos

Let's take the words of Albert Einstein as an example:

This more aristocratic illusion concerning the unlimited penetrative power of thought has as its counterpart the more plebeian illusion of naive realism, according to which things "are" as they are perceived by us through our senses. This illusion dominates the daily life of men and of animals; it is also the point of departure in all of the sciences, especially of the natural sciences.

If you want to argue that naive realism is correct then fine, but it's clearly the unscientific view. The findings of physics, neuroscience, and psychology are firmly opposed to it, despite your insistence otherwise.

and the vast majority of people are naive realists — Bob Ross

Maybe laymen and philosophers, but that's not the view of those who study perception scientifically.

Take Perception#Process_and_terminology for example:

The process of perception begins with an object in the real world, known as the distal stimulus or distal object. By means of light, sound, or another physical process, the object stimulates the body's sensory organs. These sensory organs transform the input energy into neural activity—a process called transduction. This raw pattern of neural activity is called the proximal stimulus. These neural signals are then transmitted to the brain and processed. The resulting mental re-creation of the distal stimulus is the percept.

To explain the process of perception, an example could be an ordinary shoe. The shoe itself is the distal stimulus. When light from the shoe enters a person's eye and stimulates the retina, that stimulation is the proximal stimulus. The image of the shoe reconstructed by the brain of the person is the percept. Another example could be a ringing telephone. The ringing of the phone is the distal stimulus. The sound stimulating a person's auditory receptors is the proximal stimulus. The brain's interpretation of this as the "ringing of a telephone" is the percept.

The different kinds of sensation (such as warmth, sound, and taste) are called sensory modalities or stimulus modalities.

And also this:

Indirect realism is broadly equivalent to the scientific view of perception that subjects do not experience the external world as it really is, but perceive it through the lens of a conceptual framework. Furthermore, indirect realism is a core tenet of the cognitivism paradigm in psychology and cognitive science.

Whatever "rational" grounds you might have for believing in naive realism, it is incompatible with physics, biology, neuroscience, and psychology.

I don't understand what you're trying to argue here.

I am simply explaining that we very often, both in particle physics and everyday life, observe one thing to happen and then use that thing to infer the existence and behaviour of something else.

The direct scientific realist believes that such things as dark matter, gamma radiation, and electrons cannot be perceived directly, and can only be inferred by the effects that they have on the things that can be perceived directly.

The indirect realist believes the same thing, but just adds things like apples and chairs to the list of things that cannot be perceived directly.

It's the same reasoning for everyone, they just disagree on where the line is drawn. Is it at the mental/neurological/biological, or further beyond the body?

Even the direct realist (if also a scientific realist) can believe in the existence of things that he cannot directly perceive (e.g. electrons and dark matter), and believe that these things are very unlike the things that he can directly perceive.

Whereas the direct scientific realist believes that his direct perception of a Geiger counter gives him reason to believe in the existence of radiation, the indirect realist believes that his direct perception of qualia/sense data/whatever gives him reason to believe in the existence of a Geiger counter.

Your reasoning as it stands applies to believing in anything that one cannot directly perceive, and so would call into question almost all of science (especially particle physics).

Or referring back to my original example, your reasoning would entail that it is irrational to believe that there is something moving under my bed covers.

Are you willing to commit to this?

The problem is that you have hidden the paradox, but it is there in your example. Either you trust the evidence you are using to infer whether or not there is such a thing under your bed, and what it is, or you do not. If you do, then you are trusting that evidence to give you accurate information about the "under the bed as it is in-itself": if you deny that have any such trustworthy evidence, then you have not reason to believe you can infer, other than blindly and absurdly, what is under there. — Bob Ross

I am able to believe that there is something under my covers without looking under my covers. I use what I can see to infer the existence of something that I cannot see. This is not a paradox or a contradiction or any sort of logical fallacy.

For a species to intentionally kill its own fetuses is exceedingly unnatural. — Leontiskos

Lots of things we do are “unnatural”. But then also killing one’s offspring happens in nature too. There are various species of birds that occasionally kill the weakest baby so that they can better feed the others.

Regardless, I’m not sure what “naturalness” has to do with morality.

If moral realism is correct, then there is. — Ludwig V

Moral realism can be true even if moral truths cannot be determined.

No. It depends on your standpoint on the status of a fetus. We are only charged with murder if we kill a human being. If a fetus is a human being, then it's murder. — Patterner

It doesn't depend on your standpoint on the status of a foetus. It depends on what the law says. If the law defines the crime of murder as including the killing of a foetus then killing a foetus is murder, and one is charged accordingly, otherwise it isn't and you won't be.

In both US federal and UK law, one can only murder those who have been born. This is the born alive rule.

I think consistency is important. — Patterner

Doing the right thing is more important, even if it appears "inconsistent".

I think we should be consistent. If it's murder then so is abortion. If abortion is not murder, then neither is this. — Patterner

Why?

There's an interesting question of the burden of proof here anyway. Do we have to prove that abortion is impermissible, in which case, lacking a proof, we can assume that abortion is permissible? Or do we have to prove that abortion is permissible, in which case, lacking a proof, we can assume that it is impermissible?

If we lack a proof both of the permissibility of abortion and of its impermissibility, can we just suspend judgement? I suppose we have to. In that case, there will be nothing to prevent people following their own consciences.

There is, at least at present, no conclusive argument available either way. In which case, there is no justification for a law either way and no ground to prevent people following their own consciences. — Ludwig V

Well, this is the issue I have with morality in general. I don't think any moral claims are either verifiable or falsifiable. Unlike science and maths there's just no way to prove or disprove one claim or another. We just either accept them or we don't, and then make our choices accordingly, and such choices include whether or not to pass a law to ban abortion.

I'm pro-choice.

You've left out a premiss. If deontology is true and the rules and principles are incompatible with abortion, then abortion will be impermissible. — Ludwig V

That's why I said "abortion may be morally impermissible". The point I was making is that @Samlw was assuming consequentialism in his defence of abortion. His defence fails if consequentialism is false, so to prove that abortion is permissible he must prove that its moral permissibility is determined by the consequences.

The last thing anyone should do is make a decision of this sort based on a philosophical theory — Ludwig V

Unless that philosophical theory is true. If deontology is correct and the moral permissibility of abortion is determined by rules and principles rather than by consequences then abortion may be morally impermissible even if the mother might suffer from not having an abortion.

You can say you are still preventing a human life and I agree, but the benefits out weigh the cons in my opinion. — Samlw

The counter claim is that either:

a) the benefits of an abortion do not outweigh the loss of a foetus' life, or
b) moral value is not determined by benefits, i.e. deontology is correct and consequentialism is incorrect

You are the one who claimed that it is acceptable kill a foetus if it is unconscious and unacceptable to kill a foetus if it is conscious. You must explain why being conscious matters. Asking me the question "why do we value human life over other life?" does not provide an explanation or a justification of your claim.

Why do we value human life over every other life? — Samlw

That question has no bearing on the pro-life claim that abortion is wrong. A pro-life advocate could equally be a vegan and believe that killing animals is wrong.

As it stands you haven't justified your claim that it is acceptable to kill an unconscious foetus.

I would say to that, your conscious, the foetus isn’t. So in some way you can’t use human rights in the argument because an abortion would be the same as killing something else that isn’t conscious such as a blade of grass. — Samlw

As I asked you before, why is consciousness the measure of the right to life?

Hanover offered the example of killing an unconscious person. I'll add to that the example of killing animals for food.

The matter isn't as simplistic as your reasoning would like it to be.

In my opinion that’s a weak counter because I can flip the same question and say, is it moral to take away the choice? — Samlw

It is moral to take away your choice to kill a foetus for the same reason that it is moral to take away your choice to kill me; both the foetus and I have a right to life, and our right to life takes precedence over your choice to kill us.

Around 60% of the world’s population has the right to an abortion. — Samlw

They have a legal right, sure, but the question is whether or not we have a moral right.

And in the interest of freedom and not allowing a government to have control on what life choices you want to make with your personal body, I would argue it should be a basic right. — Samlw

Do I have the basic (moral) right to kill you if you annoy me? Presumably you believe I don't. Some believe that I also don't have the basic (moral) right to kill a foetus.

So again you're just begging the question.

Additionally, it's seen as a road to euthanasia of the elderly, sick, or infirmed, which is in the same territory as readily-available state-sanctioned/assisted suicide if someone happens to convince themself (or, and this is the concern, becomes convinced by others) they should cease living, even for reasons as minimal and transient as a break-up, divorce, or loss of a job or having a bad year, month, week, or even day. — Outlander

Well that's a slippery slope fallacy.

But this also brings me back to my first point. This is a belief, and to take away rights from people simply because of that I find disgusting. — Samlw

You've begged the question by assuming that we have the right to an abortion.

I understand where people would get that from, however my counter would be that it would be wrong to kill a foetus that is conscious, I think the logic of every foetus is a potential life is correct however, to call it murder would be dramatic aslong as the foetus isn’t conscious. — Samlw

Why is consciousness the measure of the right to life?

I have never heard a compelling argument for pro-life. All of them have been based on religion or personal feelings in which my answer is always to simply not have an abortion. — Samlw

Well, we could start with perhaps a premise that we all agree with:

P1. It is wrong to kill a baby the day after birth.

The argument would then be:

P2. If it is wrong to kill a baby the day after birth then it is wrong to kill a baby the day before birth.
C1. Therefore, it is wrong to kill a baby the day before birth.
P3. If it is wrong to kill a baby the day before birth then it is wrong to kill a baby two days before birth.
C2. Therefore, it is wrong to kill a baby two days before birth.
...
etc.

This line of reasoning will entail the conclusion that it is wrong to kill a baby from the moment of conception.

To rebut it one might have to argue either that P2 is false or that there is some n such that "it is wrong to kill a baby n days before birth" is true but "it is wrong to kill a baby n + 1 days before birth" is false.