Political Crossfire Forums

[Master]

A common pro-life argument is that life begins at conception, and that a natural right to life supercedes a right to autonomy for all who are living human beings. I see that this argument is common in this forum. Here is a proof that the basic premise of that argument, that life begins at conception, is faulty.

Let P(x) be the relation "x is one human life."
Let C(x) be the relation "x is a conceptus/embryo."
Let T(x) be the relation "x will undergo or has undergone twinning."
Let Q(x) be the relation "x has been conceived less than 6 days ago."
(x) means "for all x," (Ex) means "there exists an x."
& means "and" and v means "or."
=> means "implies," while ~ means "not."

Now, we know the following:

1.) (x)(Q(x) => C(x))
2.) (x)(T(x) => ~P(x))
3.) (x)((T(x) & Q(x)) => C(x))
4.) (Ex)(T(x) & Q(x))
5.) (Ex)(C(x) & Q(x))

Now, the statement that life begins at conception is the following:
6.) (x)(C(x) => P(x))

We now prove that statement 6 produces a contradiction:

7.) T(a) & Q(a) |R:4 Existential Instantiation
8.) (T(a) & Q(a)) => C(a) |R: 3 Universal Instantiation
9.) C(a) |R: 8,7 Modus Ponens
10.) C(a) => P(a) |R: 6 Universal Instantiation
11.) P(a) |R: 10,9 Modus Ponens
12.) T(a) |R: 7 Simplification
13.) T(a) => ~P(a) |R: 2 Universal Instantiation
14.) ~P(a) |R: 13,12 Modus Ponens
15.) P(a) & ~P(a) |R: 11,14 Conjunction
16.) False |R: 15 Contradiction

For instruction on the rules used above, consider Elementary Symbolic Logic by Gustason & Ulrich.

[galba]

Master wrote: A common pro-life argument is that life begins at conception, and that a natural right to life supercedes a right to autonomy for all who are living human beings. I see that this argument is common in this forum. Here is a proof that the basic premise of that argument, that life begins at conception, is faulty.

Let P(x) be the relation "x is one human life."
Let C(x) be the relation "x is a conceptus/embryo."
Let T(x) be the relation "x will undergo or has undergone twinning."
Let Q(x) be the relation "x has been conceived less than 6 days ago."
(x) means "for all x," (Ex) means "there exists an x."
& means "and" and v means "or."
=> means "implies," while ~ means "not."

Now, we know the following:

1.) (x)(Q(x) => C(x))
2.) (x)(T(x) => ~P(x))
3.) (x)((T(x) & Q(x)) => C(x))
4.) (Ex)(T(x) & Q(x))
5.) (Ex)(C(x) & Q(x))

Now, the statement that life begins at conception is the following:
6.) (x)(C(x) => P(x))

We now prove that statement 6 produces a contradiction:

7.) T(a) & Q(a) |R:4 Existential Instantiation
8.) (T(a) & Q(a)) => C(a) |R: 3 Universal Instantiation
9.) C(a) |R: 8,7 Modus Ponens
10.) C(a) => P(a) |R: 6 Universal Instantiation
11.) P(a) |R: 10,9 Modus Ponens
12.) T(a) |R: 7 Simplification
13.) T(a) => ~P(a) |R: 2 Universal Instantiation
14.) ~P(a) |R: 13,12 Modus Ponens
15.) P(a) & ~P(a) |R: 11,14 Conjunction
16.) False |R: 15 Contradiction

For instruction on the rules used above, consider Elementary Symbolic Logic by Gustason & Ulrich.

This is kinda hard to follow. Could you put in word and explain what => means?

[The Grandmaster]

galba wrote:
This is kinda hard to follow. Could you put in word and explain what => means?

In symbolic logic, => means "implies, or entails, like Master explained before in this line:

Master wrote: ."=> means "implies,"

[The Anarchist]

galba wrote:
This is kinda hard to follow. Could you put in word and explain what => means?

As GM1 said, "=>" means "implies."

It's not that hard to follow, really. The only hard part is figuring out what the rules mean. Like 7,6 modus ponens. That stuff you can check out for yourself.

The rest can be translated by the Key that he gave at the top.

(x)(C(x) => P(x)) means:

(x) :: "For all x"
C(x) :: "x is a conceptus/embryo"
=> :: "implies"
P(x) :: "x is one human life"

So we get "For all x, 'x is a conceptus/embryo' implies 'x is one human life'"

Like I said, the rules are harder to follow.

[thefranzkafkafront]

Define life?

More importanlty define Human life?

[Prole]

Howdy, Master. Welcome to PCF. I think the one possible flaw in your reasoning is your initial supposition that:

Quote: Let P(x) be the relation "x is one human life."

I believe that many pro-lifers would argue that it does not matter if there is one life or the possibility for two (or more?), but only that a woman contains a or cells that will, if allowed to gestate without outside interference, sometimes/normally (depending on one's notion of what is "normal") become one or more mature humans.

[Master]

Prole wrote: Howdy, Master. Welcome to PCF. I think the one possible flaw in your reasoning is your initial supposition that:

Quote: Let P(x) be the relation "x is one human life."

I believe that many pro-lifers would argue that it does not matter if there is one life or the possibility for two (or more?), but only that a woman contains a or cells that will, if allowed to gestate without outside interference, sometimes/normally (depending on one's notion of what is "normal") become one or more mature humans.

Master wrote: A common pro-life argument is that life begins at conception, and that a natural right to life supercedes a right to autonomy for all who are living human beings. I see that this argument is common in this forum. Here is a proof that the basic premise of that argument, that life begins at conception, is faulty.

Other arguments require other refutations. The proof provided is sufficient for refuting the argument I mentioned.

Thank you for the welcome.

[SavannahMan]

Amazing how a single college course can convince someone that they are a lot smarter than they really are...

[The Grandmaster]

SavannahMan wrote: Amazing how a single college course can convince someone that they are a lot smarter than they really are...

Brilliant refutation there Savanna. Really impressive. :lol:

Why make such a futile and transparent attempt at demonstrating your own lack of understanding of the post? Why not go ahead and simply say “I am not smart enough to understand this post, or debate the issue, and therefore, in an attempt to make every think I’m clever, I shall insult the poster, and then in my own mind I will have won the debate.”

Go ahead and try to refute it, or debate(at least try in your case) the issue, or get out of here. How about that? :wink:

[JackarooSundown]

TheGrandmaster1 wrote: SavannahMan wrote: Amazing how a single college course can convince someone that they are a lot smarter than they really are...

Brilliant refutation there Savanna. Really impressive. :lol:

Why make such a futile and transparent attempt at demonstrating your own lack of understanding of the post? Why not go ahead and simply say “I am not smart enough to understand this post, or debate the issue, and therefore, in an attempt to make every think I’m clever, I shall insult the poster, and then in my own mind I will have won the debate.”

Go ahead and try to refute it, or debate(at least try in your case) the issue, or get out of here. How about that? :wink:

Simple, Savanna looks at a long string of symbols, sees that this person is trying to use these symbols to define life as we know it without offering any real insight or personal explanation, and then makes the statement that this person is full of himself because they hide behind the work of others yet use this work to give themself the appearance of holding an understanding of it themselves, when really we the readers have no idea whether this person actually understands or is simply quoting someone else. So the conclusion may be reached that by regurgitating what he has been taught this person is indeed not displaying any real signs of intellect, rather they are demonstrating their need to have something that other people will most likely not understand making them feel inferior and him look superior even though he himself might not understand. Even if he does posess a thorough understanding of the course, if he cannot explain what he has learned in common english, all he has is an equation.

[The Grandmaster]

JackarooSundown wrote: TheGrandmaster1 wrote: SavannahMan wrote: Amazing how a single college course can convince someone that they are a lot smarter than they really are...

Brilliant refutation there Savanna. Really impressive. :lol:

Why make such a futile and transparent attempt at demonstrating your own lack of understanding of the post? Why not go ahead and simply say “I am not smart enough to understand this post, or debate the issue, and therefore, in an attempt to make every think I’m clever, I shall insult the poster, and then in my own mind I will have won the debate.”

Go ahead and try to refute it, or debate(at least try in your case) the issue, or get out of here. How about that? :wink:

Simple, Savanna looks at a long string of symbols, sees that this person is trying to use these symbols to define life as we know it without offering any real insight or personal explanation, and then makes the statement that this person is full of himself because they hide behind the work of others yet use this work to give themself the appearance of holding an understanding of it themselves, when really we the readers have no idea whether this person actually understands or is simply quoting someone else. So the conclusion may be reached that by regurgitating what he has been taught this person is indeed not displaying any real signs of intellect, rather they are demonstrating their need to have something that other people will most likely not understand making them feel inferior and him look superior even though he himself might not understand. Even if he does posess a thorough understanding of the course, if he cannot explain what he has learned in common english, all he has is an equation.

Ahh…yes…the “I don’t understand it so the person using it must not understand it as well, and must be hiding behind it and if I say this it will show I’m not actually jealous of that person obviously superior intellect” Defense.

Nice. I’m impressed

No one had yet debated the issue. Doubtless because you cannot. I happen to know the person who posted the open to this thread. Hey guess what genius…he could take a dump and that crap would have a higher capacity for intellect that you. :lol:

Stand behind the work of others? It is he who has come up with an original refutation, and you who is using an off-the-shelf attack on the person, so who is being unoriginal now? We regurgitate what we are taught every day. Learning is done by learning from others. Every time you count your money, type, speak English, or drive, you are simply regurgitating what has been taught to you. A sad realization when your own premise comes back to bite you isn’t it. Think before posting next time, and perhaps your post won’t be a testament to hypocrisy. :wink:

[The Anarchist]

JackarooSundown wrote: TheGrandmaster1 wrote: SavannahMan wrote: Amazing how a single college course can convince someone that they are a lot smarter than they really are...

Brilliant refutation there Savanna. Really impressive. :lol:

Why make such a futile and transparent attempt at demonstrating your own lack of understanding of the post? Why not go ahead and simply say “I am not smart enough to understand this post, or debate the issue, and therefore, in an attempt to make every think I’m clever, I shall insult the poster, and then in my own mind I will have won the debate.”

Go ahead and try to refute it, or debate(at least try in your case) the issue, or get out of here. How about that? :wink:

Simple, Savanna looks at a long string of symbols, sees that this person is trying to use these symbols to define life as we know it without offering any real insight or personal explanation, and then makes the statement that this person is full of himself because they hide behind the work of others yet use this work to give themself the appearance of holding an understanding of it themselves, when really we the readers have no idea whether this person actually understands or is simply quoting someone else. So the conclusion may be reached that by regurgitating what he has been taught this person is indeed not displaying any real signs of intellect, rather they are demonstrating their need to have something that other people will most likely not understand making them feel inferior and him look superior even though he himself might not understand. Even if he does posess a thorough understanding of the course, if he cannot explain what he has learned in common english, all he has is an equation.

Why not look at the post I made earlier? It will help you read the argument. It's really not that tough. It's kinda like translating from another language, the language of reason. I have a feeling if you actually look at it and translate everything, then you won't be making such posts for fear he'll come back.

[RichardRahl]

You cannot define a human life simply with a mathematical formula. Life is not a simple formula.
That said, it doesn't matter if this ball of cells is "not living".
Once the sperm fertilizes the egg, it is its own entity. It is no longer part of the woman's body, but lives off of the mother. Therefore it is immoral to destroy it, becuase it is potential life that is not part of the woman's body...end of story.

[The Anarchist]

RichardRahl wrote: You cannot define a human life simply with a mathematical formula. Life is not a simple formula.
That said, it doesn't matter if this ball of cells is "not living".
Once the sperm fertilizes the egg, it is its own entity. It is no longer part of the woman's body, but lives off of the mother. Therefore it is immoral to destroy it, becuase it is potential life that is not part of the woman's body...end of story.


But...but.. but.... HE DIDN'T DEFINE LIFE! (And by the way, since you appear to be new...) If we are to base our actions on potential, then I suppose you would agree that it isn't murder if I decide to bury you today. After all, you are potentially a corpse and we consider it a proper thing to do with corpses.

[steen]

RichardRahl wrote: Once the sperm fertilizes the egg, it is its own entity. It is no longer part of the woman's body, but lives off of the mother. Therefore it is immoral to destroy it, becuase it is potential life that is not part of the woman's body...end of story. Why is that a valid reson for it to be immoral?

[Æ]

I believe "human life" begins at day 18. There is "life" before day 18, but it is not life with blood and a beating heart.

BTW Once upon a time, I took a fairly interesting logic course. A lot of proofs, while correct, in the end, often find their results put into question by the argument's dubious premises. For instance, Anselm's Proof uses a one-size-fits-all '>' comparison operator. As we know, there exists an infinite number of ways to compare objects A and B.

[Gilbert1908]

Master wrote: A common pro-life argument is that life begins at conception, and that a natural right to life supercedes a right to autonomy for all who are living human beings. I see that this argument is common in this forum. Here is a proof that the basic premise of that argument, that life begins at conception, is faulty.

Let P(x) be the relation "x is one human life."
Let C(x) be the relation "x is a conceptus/embryo."
Let T(x) be the relation "x will undergo or has undergone twinning."
Let Q(x) be the relation "x has been conceived less than 6 days ago."
(x) means "for all x," (Ex) means "there exists an x."
& means "and" and v means "or."
=> means "implies," while ~ means "not."

Now, we know the following:

1.) (x)(Q(x) => C(x))
2.) (x)(T(x) => ~P(x))
3.) (x)((T(x) & Q(x)) => C(x))
4.) (Ex)(T(x) & Q(x))
5.) (Ex)(C(x) & Q(x))

Now, the statement that life begins at conception is the following:
6.) (x)(C(x) => P(x))

We now prove that statement 6 produces a contradiction:

7.) T(a) & Q(a) |R:4 Existential Instantiation
8.) (T(a) & Q(a)) => C(a) |R: 3 Universal Instantiation
9.) C(a) |R: 8,7 Modus Ponens
10.) C(a) => P(a) |R: 6 Universal Instantiation
11.) P(a) |R: 10,9 Modus Ponens
12.) T(a) |R: 7 Simplification
13.) T(a) => ~P(a) |R: 2 Universal Instantiation
14.) ~P(a) |R: 13,12 Modus Ponens
15.) P(a) & ~P(a) |R: 11,14 Conjunction
16.) False |R: 15 Contradiction

For instruction on the rules used above, consider Elementary Symbolic Logic by Gustason & Ulrich.

We have been having a similar argument in another thread and while I happen to be one pro lifer that does contend life begins at conception many prolifers and indeed some Catholic theologians contend ensoulment occurs at implantation.

In either case it does nothing to negate the argument against medically induced abortion since a woman does not become aware of her pregnancy until after either event is completed.

So while it may be a very interesting debate it has no material effect on the abortion discussion whether one believes life begins at conception or implantation.

[steen]

Liberty4All wrote: I believe "human life" begins at day 18. There is "life" before day 18, but it is not life with blood and a beating heart. But why is blood and a heart indicative of 'human life"? Is that what defines us as humans?

How about a working brain (not possible until week 27) or individual function (at birth)?

[steen]

Gilbert1908 wrote: So while it may be a very interesting debate it has no material effect on the abortion discussion whether one believes life begins at conception or implantation. Yes, that debate really only has bearing on the use of some contraception.

[SavannahMan]

TheGrandmaster1 wrote: We regurgitate what we are taught every day.

Spoken like a true Democrat - usually it is harder than this to get them to admit it.

Umm "Grandmaster" - talk to me when you and "Master" have moved off campus.