Would St. Thomas Aquinas Baptize an Extraterrestrial? Edmund Michael Lazzari Marquette University edmund.lazzari@marquette.edu PRE-PUBLICATION DRAFT: Do not cite Final version published in New Blackfriars Review 99 (2018): 440-457 Abstract This paper will attempt an investigation of hypothetical intelligent extraterrestrial life from the perspective of the philosophy and theology of St. Thomas Aquinas. Section I will feature an overview of St. Thomas's relevant philosophy of human nature and the differences between human and extraterrestrial natures (even though both have material bodies and immortal souls). Section II will, with special attention to St. Thomas's De malo, treat some possibilities regarding the need for salvation (or lack thereof) in our hypothetical species. Section III will outline relevant aspects of Thomistic soteriology, especially the reasons behind the Incarnation and the role of human nature in Redemption. Section IV will feature a critique of representatives from the two major schools of scholarly thought on this issue, showing that they either disregard the necessity of a human nature for incorporation into the Mystical Body of Christ or deny the magnitude and singular importance of the Incarnation. Section V will sketch some possibilities for the soteriology of extraterrestrial life using the theology of St. Thomas Aquinas as a framework. The possibility of the discovery of intelligent extra terrestrial life raises ‐ significant questions about the role that extraterrestrials would play in the universal plan of God. Particularly in regard to the theology of original sin and redemption, the question of fallen extraterrestrials who do not share the human nature assumed by Christ is an interesting and important one for contemporary theologians. By exploring this question, not only can contemporary theology gain insights into this (currently) hypothetical case, but because this investigation touches on key aspects of Christian anthropology and soteriology, it has the potential to clarify and improve our current understanding of these central aspects of Christianity, particularly the role that human nature plays in redemption. This paper will attempt an investigation of hypothetical intelligent extraterrestrial life from the perspective of the philosophy and theology of St. Thomas Aquinas. Section I will feature an overview of St. Thomas's relevant philosophy of human nature and its application to a hypothetical intelligent extraterrestrial species, concluding that