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Research on embryonic stem cells (胚胎干细胞) is debatable because it requires the destruction of live human embryos.
Supporters find it easy to minimize the significance of this fact because the embryos are only a few days old—nothing more than "blastocysts (胚泡)".
But if it's OK to destroy 5-day-old embryos to further scientific inquiry, is it OK to destroy embryos that are five weeks old? Five months? Eight months? Science can't answer that question.
You don't have to be part of the pro-life group to have concerns about this kind of scientific research. James Thomson, the University of Wisconsin biologist has said, "If human embryonic stem cell research does not make you at least a little bit uncomfortable, you have not thought about it enough." However, the president's new order suggests we should not think too much.
Recently, supporters of embryonic stem cell research called on president to allow experiments using "surplus (多余的)" fifty frozen embryos in fertility clinics, arguing that they would be disposed of anyway. But Obama didn't limit his new policy to these fertilized eggs.
On the contrary, he left open the possibility of funding studies using embryos created specifically so their cells can be harvested. He did, however, reject another option. "We will ensure," he said, "that our government never open the door to the use of cloning for human reproduction. It is dangerous, profoundly wrong and has no place in our society, or any society."
But this position is hard to square with his claimed approach. On one hand, the president says his policy is "about letting scientists do their jobs, free from pressure". On the other, he will use pressure to keep them from doing reproductive cloning.
What this policy means is simple: It may be permissible for scientists to create cloned embryos and kill them. It's not permissible to create cloned embryos and let them live. Their cells may be used for our benefit, but not for their own.
It's the policy that is risky not just to days-old human embryos. The rest of us are sure to receive important medical benefits from this research one day. But we may lose something even more important in a moral sense.
