Is a Human Zygote an Organism?

[invest07]

It seems to me that Pro-choice arguments are primarily designed to make a person feel that abortion is OK.
Most pro-choice arguments are based on selective use of certain facts, omitting those facts that do not support the truth that abortion is death.
Let's not forget that Hitler rationalized the Holocaust. In his warped mind he was doing the world a service.
And Hitler was a huge fan of Margaret Sanger, the founder of Planned Parenthood.
Forget all the definitions and arguments on either side, many of which are designed to obfuscate and confuse.
Just use your head and your life experiences and answer this question: "Does abortion kill?"
Then ask yourself the next question: "Does anyone have the right to kill another person who is innocent?"

 

[palerider]

Many pro-lifers , in varying forms, constantly state that "it is an objective scientific fact that a human zygote is an organism/human being". I disagree. And today I plan on proving WHY.

If it is not a human being, then what species is it?

The rest of your arguments and so called proof are by your own admission and definition semantics driven not by science or objective truth, but political ideology and defense of a political position.....just as all arguments and so called proofs that pro choicers submit. We know beyond any doubt that there is no sort of metamorphosis that occurs during human gestation in which the unborn becomes something different than it was at the time it came into being...we are all exactly what we have been since we came into being, the only changes we experience are the results of becoming more mature. We know that it is born a human being and has been a human being from the time it came into existence....semantic arguments are nothing more than straw men presented by those who can not put up an argument based on objective, observable truth. You have proven nothing more by your argument than that you have no argument based upon subjective observable truth and are willing to torture words and definitions and the truth itself in order to make yourself feel that you are on the right side of an argument.

You aren't...

 

[palerider]

The definition of what is a human being,.worm, elephant or tree is that DNA which is defined (at least in humans) at conception.

with the DNA established that genrric organism may become only one thing.

Not "become" only one thing....IS only one thing. The only thing the unborn "becomes" is more mature.

i

 

[fedor50]

If it is not a human being, then what species is it?

The rest of your arguments and so called proof are by your own admission and definition semantics driven not by science or objective truth, but political ideology and defense of a political position.....just as all arguments and so called proofs that pro choicers submit. We know beyond any doubt that there is no sort of metamorphosis that occurs during human gestation in which the unborn becomes something different than it was at the time it came into being...we are all exactly what we have been since we came into being, the only changes we experience are the results of becoming more mature. We know that it is born a human being and has been a human being from the time it came into existence....semantic arguments are nothing more than straw men presented by those who can not put up an argument based on objective, observable truth. You have proven nothing more by your argument than that you have no argument based upon subjective observable truth and are willing to torture words and definitions and the truth itself in order to make yourself feel that you are on the right side of an argument.

You aren't...

Great to see you finally respond to my challenge Pale Rider and not run away.

Pale Rider in your opinion, what is the scientific definition of an organism?

Here are some definitions from the dictionaries:

From the OED: "An individual animal, plant, or single-celled life form. Also: the material structure of such an individual; an instance of this."

From the American Heritage Science Dictionary: "An individual form of life that is capable of growing, metabolizing nutrients, and usually reproducing. Organisms can be unicellular or multicellular. They are scientifically divided into five different groups (called kingdoms) that include prokaryotes, protists, fungi, plants, and animals, and that are further subdivided based on common ancestry and homology of anatomic and molecular structures."

From Merriam-Webster: "an individual living thing."

Notice how all three of these definitions rely on the term 'individual', which has yet to be defined by either of us, and cuts to the heart of the matter. I would propose the definition, still with dictionary use:

Individual: "5.Biology. a. a single organism capable of independent existence."

As such, a pre-viable foetus, embry or zygote is not biologically capable of independent existence, is hence not an individual, and is hence not an organism. Note that many of the other definitions on the linked dictionary page clearly put the matter as being subjective ("anything considered as a unit")

Pale Rider, here is my argument: It is NOT a scientific fact that a zygote fits the definition of an organism. It is a subjective opinion which means that abortion is not wrong. If you believe differently then prove that a zygote is an organism.

 

[fedor50]

Also Pale Rider, you did not defeat any of arguments at all. To defeat my argument, you must explain why a zygote is an organism, but since you can't even define 'organism' adequately you will find that pretty impossible.

All you have are assertions that you are desperately trying to pretend represents the whole of 'science'

Challenge: The assertion made by some pro-lifers that "it is an objective fact that a zygote is an organism/human being" is flawed in multiple ways

Arguments:

1. 'Organism' itself is not an objectively defined word, especially one defined as pro-lifers would like. That is, there exists no definition of 'organism' which a) includes everything which clearly is an organism b) does not include anything which is clearly not an organism c) also includes a zygote/embryo/foetus and d) is formally recognised (eg not made up on the spot by a pro-lifer trying to close all the loopholes in the definition I have thrown at them).

2. The reason for the above is that 'organism' is a word used by different scientists working in different specific fields who use the term, not as a universal identifier, but as a term to refer to some of the biological material with which they are working. This means that different scientists in different fields use different definitions of the 'organism' term (a list of at least some of the differentiating factors different scientists use is included in the OP). There is no need for a 'universal' definition of 'organism', so there is not one - at least, not yet.

3. Even if there were a 'univeral definition' for 'organism' that all scientists agreed upon, that would still not make the definition objectively scientific. Science is empirical, testable, repeatable. "What should the definition for organism be" is none of these things - the 'scientific question' that it would have to answer would be "is this definition of 'organism' accurate for all organisms?" which is obviously circular

4. There are a great number of textbooks, scientific dictionary definitions, and journal articles which imply that a zygote is not yet an organism, but that it "develops into" one. This evidence suggests that the pro-life assertion is either flawed due to subjectivity or that that it is simply flawed because a zygote is not an organism.

Evidence for the above:
No-one has been able to provide such a definition (and only one valid definition would be enough to discount that argument!)
See post #1 for lots of quoted biophilosophising.
speaks for itself.
See post #2 for lots of scientific citations

Consequence: Because of all this, the pro-life position is a matter of opinion, not of objective fact.

 

[palerider]

Great to see you finally respond to my challenge Pale Rider and not run away.

You engage in that sort of mental masturbation often?

Pale Rider in your opinion, what is the scientific definition of an organism?

An individual form of life that is capable of growing, metabolizing nutrients, and usually reproducing. Any definition beyond that is doing nothing more than injecting weasel words making the definition less precise rather than more

Individual: "5.Biology. a. a single organism capable of independent existence."

So you abandon organism entirely because clearly we are organisms from the time we are born and move to a term that is not really a scientific term but can be found in a science dictionary.

Tell me fedor50, are you capable of independent existence? According to the dictionary, independent is defined as not dependent; not depending or contingent upon something else for existence, operation, etc. You see the problem with your argument yet? You have left science and gone into semantics using words that also have meanings and the words they are defined with also have meanings. So, are you capable of independent existence? Are you not dependent upon anything else for your continued existence? Are you entirely self sufficient? How long could you live in an entirely empty space devoid of anything?

As such, a pre-viable foetus, embry or zygote is not biologically capable of independent existence, is hence not an individual, and is hence not an organism. Note that many of the other definitions on the linked dictionary page clearly put the matter as being subjective ("anything considered as a unit")

And as I pointed out, neither are us "viable" mature post natals. We all depend on something else to continue living. Unborns require exactly the same things to continue living as we....the difference being that they are not mature enough to acquire them on their own. That does not make them something other than individuals, it just makes them unable to acquire the necessities for life on their own. You have garbled your argument to the point of nonsense....by your own admission, you could not make the argument that an unborn was not a human being using the scientific term organism so you turned to the word individual...and then claim that the definitions provided by the science dictionary are not accurate and so should be replaced by the definition of the word individual. You are just going round and round in a circular fallacy.

We are human beings from the time we come into existence. We do not make experience any sort of metamorphosis during our development in which we become human beings. You are basing your argument upon how dependent the individual is rather than what the individual is which sidesteps the issue which you set out to prove. You are not capable of independent existence...you require air, you require water, you require nutrients, you require, you require, you require....we all do and so does an unborn at every stage of its development. As you mature you become more able to acquire some of those necessities but your requirement for them at every stage of your life means that by definition you are not an independent entity....so long as you require something from outside yourself in order to live, you can not, by definition, be an indecent entity.

Pale Rider, here is my argument: It is NOT a scientific fact that a zygote fits the definition of an organism. It is a subjective opinion which means that abortion is not wrong. If you believe differently then prove that a zygote is an organism.

Then your argument has failed. First, you find that you must turn to one of the words within the definition of organism in an attempt to argue that an unborn is not an individual...if you are going to weasel in that manner, then the requirement exists for you to do a more effective job at your weaseling. According to your definition of individual, the organism must be capable of independent existence. What does capable mean? ...why capable means having the ability or CAPACITY to do a thing....and what does capacity mean?...why capacity means that one has the actual or POTENTIAL ability to do a thing...and what does potential mean? See where this is going?

The fact is that you are not one bit more human than you were on the day you came into existence. You are more mature...that's all. If you want to win your argument, then you must prove that at some point between the time you came into existence and today, you underwent some sort of metamorphosis and "became" a human being but were something else before. Good luck with that.

 

[palerider]

Also Pale Rider, you did not defeat any of arguments at all. To defeat my argument, you must explain why a zygote is an organism, but since you can't even define 'organism' adequately you will find that pretty impossible.

A zygote meets the definition of an organism...it is capable of growth, metabolizing nutrients, and eventually probably reproduction. All else is semantics and leads nowhere.

Challenge: The assertion made by some pro-lifers that "it is an objective fact that a zygote is an organism/human being" is flawed in multiple ways

Before I take up that challenge I require that you first state how many zygotes are subject to abortion? Even the morning after pill does not kill zygotes. If we are talking about abortion, we are not talking about zygotes...another failure of your argument. You are attempting to represent the entirety of your pre natal development by the earliest state of your existence. How man zygotes get aborted? Answer none, unless it is a spontaneous abortion.

Consequence: Because of all this, the pro-life position is a matter of opinion, not of objective fact.

Sorry guy, but the fact that metamorphosis is not part of human development leaves you with one glaring fact...you are today, what you have been since the time you came into existence...a human being. The only change you have made is your level of maturity. Now, if you want to make the actual argument that it is ok to kill a human being based on his or her level of maturity, go ahead but you will find that you will start to sound genocidal and somewhat insane quite quickly.

 

[fedor50]

Not "become" only one thing....IS only one thing. The only thing the unborn "becomes" is more mature.

i

This is flat out FALSE.

A zygote is a totipotent cell formed by the union of a sperm and an egg. This in itself – that term ‘totipotent’ – indicates that a zygote is not yet an organism, but that it grows into one. Some quotes:

”Definition of TOTIPOTENT: capable of developing into a complete organism or differentiating into any of its cells or tissues <totipotent blastomeres>”
~Merriam-Webster Medical dictionary

”TOTIPOTENCY: 1. The ability of a cell to differentiate into any type of cell and thus form a new organism or regenerate any part of an organism; a fertilized ovum, or a small excised portion of a Planaria, which is capable of regenerating a complete new organism.”
~Stedman’s Medical Dictionary

” A distinction can be drawn between totipotent stem cells, which are capable of developing into a human being, and pluripotent stem cells, which are not so capable
…
in relation to totipotent stem cells, … each cell could develop into a human being on its own”
~ Report from the Commission to the Council and the European Parliament - Development and implications of patent law in the field of biotechnology and genetic engineering (SEC(2005) 943) /* COM/2005/0312 final */

“Totipotent cells in early embryos are progenitors of all stem cells and are capable of developing into a whole organism, including extraembryonic tissues such as placenta”
~ Tachibana M, Sparman M, Ramsey C, Ma H, Lee HS, Penedo MC, Mitalipov S. (Generation of chimeric rhesus monkeys) Cell. 2012 Jan 20;148(1-2):285-95.
Generation of chimeric rhesus monkeys. [Cell. 2012] - PubMed - NCBI

Direct evidence for totipotency is provided when an isolated blastomere is able to develop into a normal fertile offspring
~ Hilde Van de Velde, Greet Cauffman, Herman Tournaye, Paul Devroey and Inge Liebaers (The four blastomeres of a 4-cell stage human embryo are able to develop individually into blastocysts with inner cell mass and trophectoderm) Human Reproduction, Vol 23 Issue 8 Pp. 1742-1747
The four blastomeres of a 4-cell stage human embryo are able to develop individually into blastocysts with inner cell mass and trophectoderm

While I’m quoting, have some sources that say much the same thing, but without the references to totipotency:

“The zygote formed undergoes mitosis repeatedly to form the embryo which later develops into an organism”
~Textbook of Human Oral Embryology, Anatomy, Physiology, Histology & Tooth Morphology (K.M.K. Masthan), p3

"In gametic meiosis, the haploid gametes are formed by meiosis in a diploid individual and fuse to form a diploid zygote that divides to produce another diploid individual. This type of life cycle is characteristic of most animals "
~Biology of Plants (Raven, Evert, Eichorn), Chapter 9.

” During development a single cell becomes an organism composed of multiple cell types”
~ Isaac Salazar-Ciudad, Jukka Jernvall and Stuart A. Newman (Mechanisms of pattern formation in development and evolution) Development 130, 2027-2037.
Mechanisms of pattern formation in development and evolution

” Since each embryo, having the ability to develop into an individual, is valuable, it is important to minimize the decrease in survival after cryopreservation.”
~Magosaburo Kasai, Kaori Ito and Keisuke Edashige (Morphological appearance of the cryopreserved mouse blastocyst as a tool to identify the type of cryoinjury) Human Reproduction, Vol 17 Issue 7 Pp. 1863-1874.
Morphological appearance of the cryopreserved mouse blastocyst as a tool to identify the type of cryoinjury

These statements all prove that a zygote is not yet an organism but rather develops into one. In other words, a zygote is not a human being, it becomes one.

Like I said, your statement is flat out wrong. A zygote is not an individual, it BECOMES one.

If you believe differently, then give me your biological definition of an individual? Or prove to me that a zygote IS an individual?

 

[fedor50]

If it is not a human being, then what species is it?

If a zygote is not an organism, it is simply a totipotent stem cell. It is a single cell with the capability to develop into an organism (or monozygotic siblings) (or part of a chimera). It could be considered either as a stand-alone cell (in a similar way as sperm cells would no longer considered part of the male organism after ejactulation so exist individually but not as organisms), or as part of the woman’s body (similar to a transplanted organ in that it has different DNA but is still part of the greater organism).

 

[fedor50]

You engage in that sort of mental masturbation often?

Just trying to show you that science is not as black and white as you make it out to be. For example, I have heard you frequently say that Life begins at conception, but even THIS statement is patently false.

A zygote that divides into a twin can cause a second (or third, or fourth) human being to form without being the result of a second conception.

Which means that all human beings lives DO NOT begin at conception as you so frequently espouse.

An individual form of life that is capable of growing, metabolizing nutrients, and usually reproducing. Any definition beyond that is doing nothing more than injecting weasel words making the definition less precise rather than more

Theres that tricky word individual again. So tell me Pale Rider, how do you define what an individual form of life is?

So you abandon organism entirely because clearly we are organisms from the time we are born and move to a term that is not really a scientific term but can be found in a science dictionary.

Like I stated above, every definition of organism includes the word individual. And my question to you remains exact the same: How do you determine what is and isnt an individual form of life?

Tell me fedor50, are you capable of independent existence? According to the dictionary, independent is defined as not dependent; not depending or contingent upon something else for existence, operation, etc. You see the problem with your argument yet? You have left science and gone into semantics using words that also have meanings and the words they are defined with also have meanings. So, are you capable of independent existence? Are you not dependent upon anything else for your continued existence? Are you entirely self sufficient? How long could you live in an entirely empty space devoid of anything?

You are intentionally missing the point. The body of a homo sapiens is capable of maintaining life without requiring biological interaction with another organism. A zygote does not meet that vital qualification. As such, a zygote is not the body of a homo sapiens.

And as I pointed out, neither are us "viable" mature post natals. We all depend on something else to continue living. Unborns require exactly the same things to continue living as we....the difference being that they are not mature enough to acquire them on their own. That does not make them something other than individuals, it just makes them unable to acquire the necessities for life on their own. You have garbled your argument to the point of nonsense....by your own admission, you could not make the argument that an unborn was not a human being using the scientific term organism so you turned to the word individual...and then claim that the definitions provided by the science dictionary are not accurate and so should be replaced by the definition of the word individual. You are just going round and round in a circular fallacy.

Again you completely miss the point. There is a vast VAST difference between social dependence and biological dependence.

For example, cellular homeostasis is the standard by which cells are determined to be alive - and no-one is denying that a zygote is alive on the cellular level. However, homeostasis as a whole is one of the criteria by which an organism can be considered to be alive - and a zygote/embryo/(pre-viable) foetus is not capable of that.

Your arm cells are alive on a cellular level - they are even capable of reproduction. They are not an organism because, if you separated them from the rest of you, they could not maintain homeostasis. The same applies to a zygote.

We are human beings from the time we come into existence. We do not make experience any sort of metamorphosis during our development in which we become human beings. You are basing your argument upon how dependent the individual is rather than what the individual is which sidesteps the issue which you set out to prove. You are not capable of independent existence...you require air, you require water, you require nutrients, you require, you require, you require....we all do and so does an unborn at every stage of its development. As you mature you become more able to acquire some of those necessities but your requirement for them at every stage of your life means that by definition you are not an independent entity....so long as you require something from outside yourself in order to live, you can not, by definition, be an indecent entity.

We become human beings.

A skin cell cannot survive on it's own (despite being alive on a cellular level) hence each skin cell is not an organism.
A zygote cannot survive on it's own (despite being alive on a cellular level) hence each zygote is not an organism.

Then your argument has failed. First, you find that you must turn to one of the words within the definition of organism in an attempt to argue that an unborn is not an individual...if you are going to weasel in that manner, then the requirement exists for you to do a more effective job at your weaseling. According to your definition of individual, the organism must be capable of independent existence. What does capable mean? ...why capable means having the ability or CAPACITY to do a thing....and what does capacity mean?...why capacity means that one has the actual or POTENTIAL ability to do a thing...and what does potential mean? See where this is going?

Give me your definition of what an individual form of life is and how a zygote meets that qualification...

The fact is that you are not one bit more human than you were on the day you came into existence. You are more mature...that's all. If you want to win your argument, then you must prove that at some point between the time you came into existence and today, you underwent some sort of metamorphosis and "became" a human being but were something else before. Good luck with that.

Already done is one of my previous posts above. A zygote develops into an organism and I have cited several scientific sources which confirms this. It starts out as a totipotent stem cell and later on develops into an individual organism. Hence a zygote is not yet a human being.

 

[fedor50]

By the way Pale Rider, you are wrong about there being a right to life anyhow.

Let me explain to you the implications of recognizing a right to life, and then maybe you will understand why I don't consider that to be a right. Imagine I am dying in a fire. A right to life would obligate you to run into a burning building to save me, otherwise you are denying my right to life. A right to life precludes the death penalty of course, committing a crime doesn't eliminate your rights. The right to life would entitle me to food, water, clothing, and shelter whether I feel like working for it or not.

Oh and you also have to provide for my unlimited health care. If I need a kidney to live and I have a moral right to life then you have a moral obligation to give me yours. If a plague of ebola goes around and there aren't enough doses of the vaccine then the drug company is violating your right to life. If you catch someone breaking into your house you don't have a right to defend your property if it conflicts with their right to life.

It might seem like a good idea if you don't think about it too hard, but a right to life doesn't exist. The implications of such a right would infringe on the freedoms of everyone else. Each person has a responsibility to ensure their own life, and if they are unable there is no moral obligation for us to keep them alive at our own expense.

 

[palerider]

This is flat out FALSE.

A zygote is a totipotent cell formed by the union of a sperm and an egg. This in itself – that term ‘totipotent’ – indicates that a zygote is not yet an organism, but that it grows into one. Some quotes:

Actually, it is not false...and I have read the textbooks as well....far more of them, I would wager than you have yourself. I do hold medical degrees although I am not an MD...I am a DMD/DDS.

For all your definitions, are you going to argue that being a zygote is not simply a stage in human development?.. The medical dictionary defines development as the act of developing. Again, we do not metamorphose at some point in our development into something that we were not previously. We simply mature and take on characteristics that we did not previously have and that process continues long after we are born. An argument built on semantics is not even worth the time it takes to type out. For all your words, you are simply describing the first step in a long period of development of an organism... Nothing can escape that fact for you.

Again, if you want to make an honest argument, not built upon semantics, by all means do so. It must, however, take the form of the acceptability of killing a human being based on nothing more than his or her level of maturity.

 

[palerider]

If a zygote is not an organism, it is simply a totipotent stem cell. It is a single cell with the capability to develop into an organism (or monozygotic siblings) (or part of a chimera). It could be considered either as a stand-alone cell (in a similar way as sperm cells would no longer considered part of the male organism after ejactulation so exist individually but not as organisms), or as part of the woman’s body (similar to a transplanted organ in that it has different DNA but is still part of the greater organism).

Of course it is an organism...or are you going to argue that it is not capable of growth, or metabolizing nutrients....would you care to argue that it does not, in fact, send out a chemical message to its mother's body advising her of its existence so that her immune system does not attack it?....would you care to argue that it's DNA is not distinctly different from either it's mother or it's father? Can you make any rational argument whatsoever that it is not precisely what it is?....it is the first stage of development of a human being. Now, if you can provide some evidence that once the zygote divides, it has, in fact metamorphosed into something it wasn't before other than a human being in the earliest stage of development, by all means, lets see the work.

 

[palerider]

Just trying to show you that science is not as black and white as you make it out to be. For example, I have heard you frequently say that Life begins at conception, but even THIS statement is patently false.

Of course it is...when you whittle past all of the semantics, it is exactly that black and white. Ask yourself, is the zygote alive? If it is not, then you are correct that the life did not begin once conception was complete. You clearly, can not make that argument though, so you are left perhaps wishing that the life is not begun at the time conception is complete but it is a fruitless and doomed wish.

A zygote that divides into a twin can cause a second (or third, or fourth) human being to form without being the result of a second conception.

So what? In our earliest possible stage of development we are capable of asexual reproduction. Goodie for us. We are gaining and losing abilities all along our developmental journey. For a very short period of time, we have that ability....it doesn't change what we are at that stage of our lives.

Again you completely miss the point. There is a vast VAST difference between social dependence and biological dependence.

Sorry, it is you who has missed the point. Shallow thinking. I didn't even consider social dependence. Would you like to try and argue the point that you are not biologically dependent on the lives of other living things for your very survival? Good luck with that one

We become human beings.

What species were we before we "become" human beings. Even one celled organisms are bona fide members of some species....which one did you belong to before you "became" homo sapiens sapiens?

Give me your definition of what an individual form of life is and how a zygote meets that qualification...

I don't have a definition. I accept the one that medical science provides and don't try to weasel my way around it. An individual form of life that is capable of growing, metabolizing nutrients, and usually reproducing. At even our earliest stage there is no argument that we are alive, we are capable of growing and metabolizing nutrients. We are what we are.

 

[palerider]

By the way Pale Rider, you are wrong about there being a right to life anyhow.

Let me explain to you the implications of recognizing a right to life, and then maybe you will understand why I don't consider that to be a right.

Of course you consider it to be a right. You are as transparent as glass. Life must be so easy for sociopaths. Look at all the effort you have put into trying to deny that a fresh shiny new human being is something other than what it is so that you can convince yourself that you are not a sociopath for wanting it to be OK to dispose of it for any reason. If you didn't believe there was a right to live, then you could make the amoral sociopathic argument in good conscience....you didn't, therefore you believe in a right to life....as if belief were required...it is enumerated into our constitution.

Imagine I am dying in a fire. A right to life would obligate you to run into a burning building to save me, otherwise you are denying my right to life. A right to life precludes the death penalty of course, committing a crime doesn't eliminate your rights. The right to life would entitle me to food, water, clothing, and shelter whether I feel like working for it or not.

Don't we, as a society, pay people to do exactly that? Don't firemen die all the time trying to save someone who is dying in a fire? You have a right to live but not at the expense of my life....your right to live does not trump my own right which is why I say clearly that if a child represents a genuine (as opposed to a statistical) threat to its mother's life then she has every right to self defense. Any genuine threat can be determined well before the threat becomes acute.

Oh and you also have to provide for my unlimited health care. If I need a kidney to live and I have a moral right to life then you have a moral obligation to give me yours. If a plague of ebola goes around and there aren't enough doses of the vaccine then the drug company is violating your right to life. If you catch someone breaking into your house you don't have a right to defend your property if it conflicts with their right to life.

Now you have left semantics and are just being stupid and sarcastic. If that is the best you can do, then you may as well just hang it up...you have lost.

It might seem like a good idea if you don't think about it too hard, but a right to life doesn't exist. The implications of such a right would infringe on the freedoms of everyone else. Each person has a responsibility to ensure their own life, and if they are unable there is no moral obligation for us to keep them alive at our own expense.

Of course it does, it is enumerated in black and white in our constitution and the concept of one individual's rights ending where they infringe on another's are quite clear. Your life isn't any more important than mine and there is no requirement that I forfeit my life so that you can keep yours....but by the same token, I certainly can not end your life because you are an inconvenience to mine. Are you really so obsessed and blinded by your need to feel that you are on the right side of this discussion that you are going to try to argue that the words don't exist in that document?

I know that you thought that you had an argument but like all other pro choices, your argument was shallow in the extreme...weasel words and semantics do not a rational, philosophical argument make. You have engaged in, what I would call, a poor to mediocre piece of sophistry that I doubt even convinced you, yourself if you are even moderately intelligent.... but an actual rational argument that we are ever something other than human beings?...or that it is OK to kill another human being who represents an inconvenience to you?....you haven't even come close.