Since this is a subject often discussed here, I thought you might all be interested in the following article:-
http://www.bbc.co.uk/religion/ethics/abortion/embry_viable1.shtml
When does a foetus get the right to life?
Much argument in the abortion debate is over when the foetus becomes sufficiently human to have the right to life.
Of course, this issue is irrelevant to those who think the foetus has a right to life from the instant of conception.
But for everyone else - and particularly for those who draft laws regulating abortion - it's one of the key points.
Spelling out the problem
Everyone agrees that adult human beings have the right to life. Many people would say that the fertilised cell resulting from conception does not have the right to life. Therefore the right to life is acquired sometime in between those two points, and the big question is "when?"
It's sometimes put in another way as the question "when does life begin?" referring to the sort of life that we regard as precious.
A strange idea
Unfortunately there's no agreement in medicine, philosophy or theology as to when life really begins, let alone what stage of foetal development should be associated with the right to life.
That isn't surprising, because the idea that there is a precise moment when a foetus gets the right to live, which it didn't have a few moments earlier feels very strange.
And when you look closely at each of the suggested dates, they do seem either arbitrary or not precise enough to decide whether the unborn should have the right to live.
Nonetheless, as a matter of practicality many abortion laws lay down a stage of pregnancy after which abortion is unlawful (because the foetus has a right to life), and the dates chosen are usually based on viability.
Moral issues
Because of the difficulty of deciding at what stage a foetus becomes a being with the right to life, some people argue that we should always err in favour of an earlier date.
They say that if we don't know whether the foetus has reached a stage where it has the right to life, we should assume that it does have the right to life, as this will do least damage to the foetus.
Relevance
Some people say that if the foetus is not a person, then abortion deserves no condemnation. This oversimplifies the issues. Even if the foetus is not a human being, it is clearly regarded by most people and most societies as something special that should not be casually discarded.
The stages of foetal development
Various points have been suggested as the point that the foetus gets the right to life:
conception - the moment the egg is fertilised. The 'Catechism of the Catholic Church' states that the embryo must be treated as a person from conception and so do many others who oppose abortion...
this is an entirely logical point to choose as the beginning of human life
it's one of the few points that isn't arbitrary or difficult to judge, as an egg is either fertilised or not
at this point the fertilised egg contains the full genetic code of a human being
not a very good argument, since so do all the cells of the body
but it only marks the beginning of biological life
many people believe that biological life is not sufficient to give the foetus the right to life
Implantation - when the fertilised egg is implanted in the womb. This happens about a week after conception.
this point is easy to identify
but this point is just as arbitrary as any other date
'quickening' - when the foetus first moves in the womb. This happens about 16 to 17 weeks after fertilisation.
the idea came from a now abandoned Christian theory that this was the moment that the foetus got its soul
for example St. Augustine made a distinction between embryo inanimatus, not yet endowed with a soul, and embryo animatus, endowed with a soul
without "ensoulment", quickening does not seem to have any merit as the start time for human rights
medically, the time of quickening is influenced by irrelevant factors, such as the number of previous pregnancies that the mother has had
Aristotle suggested 40 days (males), 90 days (females) was the time
these are purely arbitrary times - and there's certainly no reason for males and females to get the right to life at different stages of development
the idea itself came out of Aristotle's three-stage theory of life: vegetable, animal, rational. The vegetable stage was reached at conception, the animal at 'animation', and the rational soon after live birth.
the time when tissues in the foetus separate into different types
this covers a lengthy period of time
tissue type separation doesn't seem to have any obvious moral - so the choice of this as the key date is probably because the increasingly human appearance of the foetus causes us to feel increasingly protective of the foetus
the first sign of brain activity
this is a logical point, as it marks a necessary state for many of the characteristics that some people think a 'moral person' has to possess
but brain activity at this stage is no more than a precondition - it doesn't demonstrate that the foetus is actually 'conscious'
viability - the stage when the foetus could survive outside the womb
this is the most common criterion used in drafting laws regulating abortion
whether a foetus can survive outside the womb depends on:
the state of medical science
the medical facilities available at a particular location
the competence or willingness of the mother (or some other care-giver)
the gender of the foetus
the race of the foetus
there is something unsatisfactory about a being's rights being determined by its sex or race, the state of medical science, the state of medical facilities at a particular location, or the type of mother it has
birth
This appears to be a clear and unambiguous date, but there is disagreement on the point at when a baby is actually born. Is it:
when part of the baby is outside the mother's body?
when the whole baby is outside the mother's body?
or when the placenta separates from the womb and the foetus has to rely on its own resources to keep alive?
Some people say that it's odd that a being's right to life should depend on whether a being is located inside or outside the womb
But they miss the essential point which is that at birth the baby begins to exist independently of the mother
Vagueness is a virtue
As we've seen, there are difficulties with choosing a precise point when the unborn gets the right to live.
Although it's uncomfortable to be so imprecise, the right answer may lie in accepting that there are degrees of right to life, and the foetus gets a stronger right to life as it develops.
This answer has the value of reflecting the way many people feel about things when they consider abortion: the more developed the foetus, the more unhappy they are about aborting it, and the more weight they give the rights of the foetus in comparison with the rights of the mother.
This view is sometimes called 'gradualism'.
http://www.bbc.co.uk/religion/ethics/abortion/embry_viable1.shtml
When does a foetus get the right to life?
Much argument in the abortion debate is over when the foetus becomes sufficiently human to have the right to life.
Of course, this issue is irrelevant to those who think the foetus has a right to life from the instant of conception.
But for everyone else - and particularly for those who draft laws regulating abortion - it's one of the key points.
Spelling out the problem
Everyone agrees that adult human beings have the right to life. Many people would say that the fertilised cell resulting from conception does not have the right to life. Therefore the right to life is acquired sometime in between those two points, and the big question is "when?"
It's sometimes put in another way as the question "when does life begin?" referring to the sort of life that we regard as precious.
A strange idea
Unfortunately there's no agreement in medicine, philosophy or theology as to when life really begins, let alone what stage of foetal development should be associated with the right to life.
That isn't surprising, because the idea that there is a precise moment when a foetus gets the right to live, which it didn't have a few moments earlier feels very strange.
And when you look closely at each of the suggested dates, they do seem either arbitrary or not precise enough to decide whether the unborn should have the right to live.
Nonetheless, as a matter of practicality many abortion laws lay down a stage of pregnancy after which abortion is unlawful (because the foetus has a right to life), and the dates chosen are usually based on viability.
Moral issues
Because of the difficulty of deciding at what stage a foetus becomes a being with the right to life, some people argue that we should always err in favour of an earlier date.
They say that if we don't know whether the foetus has reached a stage where it has the right to life, we should assume that it does have the right to life, as this will do least damage to the foetus.
Relevance
Some people say that if the foetus is not a person, then abortion deserves no condemnation. This oversimplifies the issues. Even if the foetus is not a human being, it is clearly regarded by most people and most societies as something special that should not be casually discarded.
The stages of foetal development
Various points have been suggested as the point that the foetus gets the right to life:
conception - the moment the egg is fertilised. The 'Catechism of the Catholic Church' states that the embryo must be treated as a person from conception and so do many others who oppose abortion...
this is an entirely logical point to choose as the beginning of human life
it's one of the few points that isn't arbitrary or difficult to judge, as an egg is either fertilised or not
at this point the fertilised egg contains the full genetic code of a human being
not a very good argument, since so do all the cells of the body
but it only marks the beginning of biological life
many people believe that biological life is not sufficient to give the foetus the right to life
Implantation - when the fertilised egg is implanted in the womb. This happens about a week after conception.
this point is easy to identify
but this point is just as arbitrary as any other date
'quickening' - when the foetus first moves in the womb. This happens about 16 to 17 weeks after fertilisation.
the idea came from a now abandoned Christian theory that this was the moment that the foetus got its soul
for example St. Augustine made a distinction between embryo inanimatus, not yet endowed with a soul, and embryo animatus, endowed with a soul
without "ensoulment", quickening does not seem to have any merit as the start time for human rights
medically, the time of quickening is influenced by irrelevant factors, such as the number of previous pregnancies that the mother has had
Aristotle suggested 40 days (males), 90 days (females) was the time
these are purely arbitrary times - and there's certainly no reason for males and females to get the right to life at different stages of development
the idea itself came out of Aristotle's three-stage theory of life: vegetable, animal, rational. The vegetable stage was reached at conception, the animal at 'animation', and the rational soon after live birth.
the time when tissues in the foetus separate into different types
this covers a lengthy period of time
tissue type separation doesn't seem to have any obvious moral - so the choice of this as the key date is probably because the increasingly human appearance of the foetus causes us to feel increasingly protective of the foetus
the first sign of brain activity
this is a logical point, as it marks a necessary state for many of the characteristics that some people think a 'moral person' has to possess
but brain activity at this stage is no more than a precondition - it doesn't demonstrate that the foetus is actually 'conscious'
viability - the stage when the foetus could survive outside the womb
this is the most common criterion used in drafting laws regulating abortion
whether a foetus can survive outside the womb depends on:
the state of medical science
the medical facilities available at a particular location
the competence or willingness of the mother (or some other care-giver)
the gender of the foetus
the race of the foetus
there is something unsatisfactory about a being's rights being determined by its sex or race, the state of medical science, the state of medical facilities at a particular location, or the type of mother it has
birth
This appears to be a clear and unambiguous date, but there is disagreement on the point at when a baby is actually born. Is it:
when part of the baby is outside the mother's body?
when the whole baby is outside the mother's body?
or when the placenta separates from the womb and the foetus has to rely on its own resources to keep alive?
Some people say that it's odd that a being's right to life should depend on whether a being is located inside or outside the womb
But they miss the essential point which is that at birth the baby begins to exist independently of the mother
Vagueness is a virtue
As we've seen, there are difficulties with choosing a precise point when the unborn gets the right to live.
Although it's uncomfortable to be so imprecise, the right answer may lie in accepting that there are degrees of right to life, and the foetus gets a stronger right to life as it develops.
This answer has the value of reflecting the way many people feel about things when they consider abortion: the more developed the foetus, the more unhappy they are about aborting it, and the more weight they give the rights of the foetus in comparison with the rights of the mother.
This view is sometimes called 'gradualism'.
