本文主要介紹中世紀大思想家聖多瑪斯．亞奎納建立在古典靈魂觀基礎之上的胚胎發生哲學，以其「相繼賦魂」及「延後人化」的理論，嘗試會通當代相關自然科學領域的成果，並結合天主教會訓導，推動當代生命倫理以位格身份的確立展開胚胎問題的思考，並指出從位格倫理向生命倫理的發展路向。

The article mainly introduces mediaeval great thinker St. Thomas Aquinas' philosophical embryogenesis in terms of the ancient psychology (soul theory). It attempts to integrate his theories of Successive Ensoulment and Delayed Hominization with correlative contributions of contemporary natural sciences and refers also to the teachings of Catholic Church in order to facilitate the bioethical reflection on embryo by the definition of personhood and indicate the approach from the so-called “personal” ethics to “bio”-ethics, namely, the ethics of life.