With regard to abortion, I agree at least partly with Peter Singer. I'd encourage anyone who's interested in issues surrounding abortion and euthanasia who hasn't looked him up already to do so. His views are quite controversial, but even so I respect them for actually being consistent, unlike so many others involved in these debates. I went to look him up again, to refresh my memory so I wouldn't post anything factually wrong here, and I saw this quote:
[The argument that a fetus is not alive] is a resort to a convenient fiction that turns an evidently living being into one that legally is not alive. Instead of accepting such fictions, we should recognise that the fact that a being is human, and alive, does not in itself tell us whether it is wrong to take that being's life.
I tend to agree with this. I'll focus on the first part here. Basically, as far as I can tell, any attempt to define or delimit what it means to be human
( or if you prefer, a human being, or a person ), fails in one way or another. It's either too broad or it's too narrow. The lines are blurry, the limits often arbitrary. Conception isn't some sort of sharp, instant divide. I also don't think you're any more or any less human at, say, day 23, to pick a number, than at day 22 and 23 hours. In short, I think using more detailed terms is healthy. If you want to get anywhere in a discussion like this, you need to be specific, because otherwise you're going to end up saying either more, or less, than you intended. I mean, if you say a human embryo is a person, you've got a whole range of legal implications. It's like trying to navigate a minefield.
I'm not sure I'm saying anything that hasn't already been covered, so I'll just leave it at that for now. And, again - Peter Singer.