There is a difference between a temporary belief until better evidence comes in, and a firm belief regardless of evidence. Not everyone has a firm belief regardless of evidence, and I don't think anyone should have such a belief. Any such belief may interfere with science (unless it is sufficiently meaningless), thus making the two almost always at odds on one thing or another.
So you think your belief is better than other beliefs. You even think people should not have other beliefs. How does that make you different from any zealous creationist militant christian? (Except for the well known fact of life that your belief is way better than theirs)
Don't presume to say what I think, because that is not at all what I said. Imposing my belief system is not the same as deconstructing the fallacies and exposing the harm of other beliefs. Telling me that I'm going to go to hell if I'm not a christian, and thus I better become a christian, would be imposing a belief. Telling me that I have a faulty method of doing a math problem would not be.
As for the living status of an unborn child (since you asked), it's actually somewhat simple depending on how you measure life and what you value in life. I value the ability to think, feel pain, believe, and so forth. A blob of cells that can't do this I don't value as a person. This would mean that when the nervous system develops from the notochord, or perhaps more importantly when the brain is distinct and functioning. Brain waves can be recorded at about 6 wks, but it can't feel pain until about 12 wks. To be safe, I'd not take it out after 6.
The legal limit here is 22 to 24 weeks. That makes you a pretty conservative interfering believer, standing in the way of people who want a choice. If you say you don't interfere, then you should be okay with killing babies 20 years after birth as well, right? Or not? If so, where's the limit then?
I'm feeling militant
Thanks? I'm a little fuzzy on the times that specific things happen and their relevance, so I used the conservative estimates. With better data I could change my mind. I have a feeling that the people who set that limit know more than I do. Also, The legal limit you present is for abortions, correct? Pro-life (anti-abortion with a prettier name) activists would protest that. Stem cell research (how this started, remember?) uses them at far less than that (I read somewhere around 2 wks). Legally, by the way, it is not considered a baby with rights until it is born, so both of those are conservative in a way.
Killing people 20 years after birth is actually a good point to bring up. Unfortunately that line travels us down a long path of when killing others is ethical. We could go into the death penalty, euthanasia, the brain-damaged, suicide, and all sorts of things. However, I think it's fair to say that ethically we generally consider killing the young to be (a lot) worse.