Exodus 21:22-23 – If an attack on a woman causes a miscarriage the attacker must pay a fine. If he causes serious damage to the mother it’s “an eye for an eye, a tooth for a tooth”. This indicates that a fetus does not have equal standing under God’s law.

Leviticus 27:6 – Monetary values are assigned to lives according to age and gender. Lives under one month old have no value.

Numbers 5:21-21, 27-28 – A potion given to the Israelites by God is used to determine paternity. If the father is not the husband, an abortion occurs. god clearly places no value on a fetus that is not the result of union between husband and wife.

Genesis 38:24 – God’s law states that if a woman is pregnant and is to be executed, there is to be no waiting for the fetus to be born. It is counted as part of the mother and she burned to death with it still in her womb.

Food for thought.
P.S. Not sure if you’ve ever read Freakonomics, but there’s a chapter in there about how legalisation of abortion in the USA was directly related to the drop in crime rates in the early 1990s. It’s not arguing for or against abortion, but it’s worth reading.

A foetus is a human – the unique product of a sperm and egg. It is a living entity, and without aggressive medical intervention, it will likely grow into a baby and be born.

You seemed to miss my main point which is this; if an organism has a right to life only if it presently is sentient. Then people who are temporarily unconscious do not have a right to life. A person in a temporary coma for example cannot be woken up at the time he is in the coma and hence is presently not sentient. Yet it is wrong to kill such people, hence present possession of sentience is not a necessary condition for a right to life. This I think is a further problem alongside the one I have already mentioned, that of find any non-contrived reason for accepting the sentience criteria in the first place.

You state

“The fact that a fetus may at some point become sentient is as relevant to its rights as the fact that a sperm may contingently become sentient after some period of development. I will certainly grant that pre-sentient fetuses have as much right to life as do sperm.”

This objection assumes that sperm and ova will become sentient just like a fetus will but this assumption is false. (Jim Stone refutes it in his article “Why Potentiality Matters” Canadian Journal of Philosophy Vol 17. 4 (1987) the same point is made in Buckle’s “Arguing From Potential” Bioethics 2 (1988) ) Those ethicists who appeal to the fetus potential to be sentient understand it to be the claim that: If an fetus grows normally there will in the future be a sentient being who once was the pre-sentient embryo. Hence sperm and ova are potentially sentient, in the relevant sense, only if sentient foetuses once were sperm. But it’s not true that a fetus once was a sperm cell. If you trace the development of fetus backwards to conception you find that prior to this time there were two organisms a sperm and an ova which merged to form the conceptus. To identify the conceptus with the sperm seems arbitrary. There appears no reason for identifying the fetus with the sperm that pre-existed it than there is for identifying the fetus with the ova.
To avoid arbitrariness you can identify it with both sperm and ova, but then you get you get paradoxes this is because identity relationships are transitive. That is, if X is identical with Y and Y is identical with Z, then X and Z are identical. Hence if the fetus is identical with both the sperm and ova then the sperm and ova are identical organisms which are false. The point is that it’s very difficult ( if not impossible) to trace identity through fussions of organisms into one organism.

On the other hand the presentiment fetus and the post sentient fetus are the same organism in different stages of development. After 14 days there is no fusions of different organisms into one which would call identity of a pre-sentient fetus with a sentient fetus into question.

I don’t think he meant sperm were sentient. Thats what Catholics believe and he doesn’t seem very Catholic.

Moreover, the fact that a fetus cannot be awakened does not mean that it, unlike a sleeping man, lacks potential sentience. What if, in the normal course of events, it took a man several months to wake up? Your only angle seems to be that it will take a fetus longer to gain sentience than a sleeping man. That the sentience of the two obtains via different processes hardly seems morally relevant.

A sleeping man is sentient, even if the sentience is potential. He can be wakened. A fetus prior to quickening is not sentient. It cannot be wakened by some stimulus.

The fact that a fetus may at some point become sentient is as relevant to its rights as the fact that a sperm may contingently become sentient after some period of development.

I will certainly grant that pre-sentient fetuses have as much right to life as do sperm.

First, as CN alluded to is that if a person is unconscious, asleep, under a general anaesthetic, in a coma, it would follow that they would have no right to life.

Second, you give no argument for this position, except to say that you are aware of no non-religious argument for the immorality of killing a pre-sentient fetus.

This surprises me. One of the most important arguments in the literature is written by an atheist, Don Marquis, who argues that it is wrong to kill a pre-sentient fetus because a pre-sentient fetus, an infant (also someone asleep, under anaesthetic or in a coma) has the same future as an adult and what makes killing an adult wrong is that it deprives them of a valuable future.

This is probably the most widely anthologised article on abortion. Marquis’s position may be mistaken, but that needs to be shown by argument and your own position given reasons in its favour.

To simply assert that you have never heard a secular argument for a particular position, especially when such an argument is one of the central matters discussed in the literature on abortion is inadequate.

I could also point out that in addition to Marquis, there are secular arguments for the idea that it is wrong to kill a fetus when its brain starts functioning around 6-8 weeks gestation – Baruch Brody provides an example, then there are the potentiality based arguments of Jim Stone and Phillip Devine (all secular).

Finally, as I pointed out in previous comments, the fact that there is no-good non-religious arument for a position does not mean that there is no good argument.

The very fact that abortion is such a contentious issue tells us that some people do find the killing of a fetus as repugnant as infanticide.

The repugnance argument can be turned on its head. Many people have considerable more repugnance towards people who beat little children to death than they do towards gang members killing each other. Does it follow that adult gang members are less human than children?

Further, sociological evidence tells us that outside Christian, Jewish and Muslim cultures, there is not always regpugnance towards infanticide. It was because of Christian teachings about abortion and infanticide that western society developed this repugnance in the first place.

You say that a child and an adult do not have the same rights. You are correct, children do not have a right to vote, have sex or marry. However, they do have a right to not be killed. It is this right that is relevant in the abortion debate.

Finally to your point about miscarriages, we only investigate homicide if we have probable cause to assume that a crime has been committed. Given how common miscarriage is the mere fact that one occurs would not constitue probable cause in and of itself.

I would also point out to you that your argument here trades on the idea that investigating a woman who has had a miscarriage would be deeply upsetting precisely because miscarriage is a traumatic upsetting event. If a fetus is not a human being, this should not be the case.

In fact, given our practice of abortion on demand and the assumption that feticide destroys pre-human tissue, having a miscarriage, by your reasoning, is no different to ejaculating or menstruating so why would anyone be upset by it?