本文評析人類胚胎幹細胞研究所引起之生命倫理爭議。在胚胎幹細胞研究所招致的諸多批評中，最值得注意的有下列三項：(1)胚胎幹細胞研究導致胚胎被毀，因為胚胎是人，所以摧毀胚胎說等於殺人；(2)胚胎幹細胞研究使胚胎變成了、或生而為達成其他（非生育）目的之工具，而胚胎的工具化恐將使社會成員愈來愈不尊重人類生命，使得整個社會的生命倫理情境不斷沈淪；(3)幹細胞研究者所欲使用的胚胎複製技術，將促成複製人的到來，進而引領人類走向危險的美麗新世界。本文檢討這些批評及其所涉及的三項生命倫理課題，並提供對相關問題的看法。作者指出，胚胎幹細胞研究的倫理爭議，不宜與墮胎爭議混為一談，因為堕胎所涉及的是懷孕婦女與胎兒之問的特殊關係，而研究者對人類胚胎的毀損與利用，則牽涉到該項研究的潛在貢獻與各種其他考量之間的輕重權衡。作者進一步檢視關於胚胎工具化、胚胎複製技術等問題的辯論，並區分幾種具代表性的觀點。而作者所採取的觀點是：政府應在開放胚胎幹細胞研究的同時，對其進行嚴格的監督與管制，如此才得以避免其可能造成的不良後果。

The question of whether or not to proceed with human embryonic stem cell research is an ethically serious and difficult one. This article examines three major ethical issues involved in human embryonic stem cell research, concerning, respectively, the moral status of embryos, the instrumentalization of embryos, and the cloning of embryos for research purposes. It is argued that the identification of the human embryo as a person carries far-reaching consequences, some of which are not only inconsistent with the penalty provided in abortion legislation, but are deeply at odds with most people's moral intuitions. Those who speak of slippery slopes, the instrumentalization and desensitizing of human life, are right to worry but wrong to believe that embryonic stem cell research necessarily opens us to such dangers. We should allow research to proceed subject to ethically appropriate regulations. This approach offers the better hope of harnessing biomedical progress with responsibility.