Petrus,
I'm having a hard time following your reasoning. People that support abortion generally support it because they claim the fetus isn't a human being yet. Gawain is offering evidence that at week 21, it is indeed a human being. You turn around and accuse him of manipulating people's emotions. Which is it? Are you looking for evidence of humanity, or are you looking for people to make the argument for viablility in a vacuum of pure reason, with nothing so confusing as empirical observations?

Kurki,
I think you're 100% correct. The abortion debate really is a 'when does life begin' debate, because I've never met anyone who claims it's okay to kill an infant later the same day it's been born. I've never seen a good argument made for 'life begins at birth', but I would be interested to hear it. This is a really difficult question, because the definition of what it means to be alive is widely argued. Some bio-ethicists claim that viruses aren't alive. Others have argued that fire is. Personally, I hold that life begins with viability. And I know this can be viewed as a cop-out, because the age of viability is dependent on the available technology, but let's face it folks, there aren't going to be any simple answers to these questions. We need something that at the very least is definable. The solution we have in the USA right now is abominable and does not work.