Hominization theory speculates on the process and chronology of a human embryo’s ensoulment.Aristotle, a key ancient Greek thinker, presented his own hominization theory based on his hylemorphic metaphysics and pioneering researches in embryology. ThomasAquinas, a medieval philosopher and theologian, built his Christian and Catholic hominization theory on the foundations laid down by Aristotle. The contemporary Roman Catholic Church, with its own prolife, anti-abortion and anticontraception agenda, modified the Aristotelian and Thomistic hominization theories by allegedly benchmarking on recent developments in human embryology. This paper uses the archeological and genealogical methods, as developed by the French poststructuralist and postmodernist philosopher Michel Foucault, in reexamining these three hominization theories as discourses, in comparing and contrasting their epistemic contexts, and in peering into their respective genealogies. Contrary to common assumptions, these three hominization theories have very few elements in common and are actually divergent. The underpinning intention of this paper is to demonstrate the strengths and weaknesses of the contemporary Roman Catholic Church’s hominization theory.