St. Thomas Aquinas on Disability & Profound Cognitive Impairment

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St Thomas Aquinas on Disability and Profound Cogntive Imapirment (Abstract) This dissertation raises a question regarding the relationship between the condition of the body, moral virtue, and human flourishing. Our main objective is to reconstruct Aquinas’s theological understanding of corporeal infirmity in order to depict, in broad outline, a Thomistic theology of disability and cognitive impairment. A prominent concern in this investigation is to understand, according to Aquinas, the significance of the body in the perfection of human activity towards the realization of our natural and supernatural end, as well as the implications of Aquinas’s view with respect to persons who have a profound and utterly debilitating cognitive impairment. Remarks on disability and impairment are found throughout Aquinas’s Summa Theologica and his treatise De Malo. Although Aquinas did not compose an ex professo theological tract on ‘disability,’ the integral and systematic character of what he says about these matters implicates the whole of his thought and, in particular, his moral theology. In his Summa, Aquinas brings together careful scriptural exegesis, patristic and medieval sources, as well as the best philosophy of his day. The result, with respect to our theological understanding of corporeal infirmity, is an innovative and far-reaching depiction of a properly Christian understanding of these matters. In the experience of corporeal infirmity, we are confronted with a question that pertains directly to the proper object of moral theology. [1] Regrettably, there remains a notable lacuna in contemporary Aquinas studies and Thomistic moral theology on the topics of disability and cognitive impairment. In particular, the vulnerability of human beings to the evil (malum poenae) of corporeal infirmity and the moral significance of profound affliction has received very little attention. We intend that the interpretive work of this investigation in the theology and philosophy of Aquinas will help address that lacuna. We can describe the relevance of this project to the work of Thomistic moral theology in stronger terms. Aristotle’s great insight was to understand that any description of the good life and the happy life of the human being cannot be separated from an account of how that life is possible for the kind of beings that we are, i.e., the biological constitution of the rational animal. Aquinas appropriated that Aristotelian thesis and revised it in the light of the Christian doctrine of creation. So conceived, integral to moral reasoning in the Thomistic theological tradition is the ability to account for how faithful discipleship, Christoformic virtue, and cruciform love are possible for the kind of beings that we are, i.e., our creaturely constitution: mortal rational animals made in the image of God. Moreover—and here are the stronger terms mentioned above—no moral theology can pretend to any measure of seriousness if it does not account for how discipleship, Christoformic virtue, and cruciform love is possible for the created rational animal while contingently and unequally bearing the corporeal wounds of original sin. Specifically, grace restores and heals what was lost at the fall (original justice), but baptism does not immediately heal the wounds of original sin in our bodies (our trust in Christ entails the hope of bodily resurrection). Yet, Christ calls us to discipleship, virtue, and love as we await the restoration and healing of our wounded bodies in the consummation of glory. On this understanding of the human predicament, our present concern is to provide a theological account of what it means for the created rational animal to flourish with respect to its natural and supernatural ends, even as it continues to bear the corporeal wounds of original sin. The four chapters of this dissertation are divided into two parts. Part 1 (chapters 2 and 3) is concerned with Aquinas’s understanding of the first perfection or creaturely integrity of the human being. The objective is to depict Aquinas’s account of the human being by showing how he made use of Aristotle and Augustine. Towards that end, chapter 2 focuses on Aristotle’s metaphysical biology and his account of human defect; Aquinas’s Augustinian doctrine of creation; and Aquinas’s appropriation and subversion of Aristotle’s account of ‘defective human beings.’ Of particular importance in chapter 2 is Aquinas’s engagement with the forms of irrational human behavior described in Aristotle’s Nicomachean Ethics and Aristotle’s theory of natural slavery outlined in Book 1 of the Politics (i.e., despotic rule over an essentially defective human being who is incapable of discursive reasoning). Special attention is given to the precise metaphysical defect of the ‘slave by nature,’ as distinct from other forms of human defect on Aristotle’s terms. We show how Aquinas subverts Aristotle’s notion of natural slavery (by rejecting the possibility of essential defect), while revising Aristotle’s phenomenological description of the natural slave’s dispositional dependency under the moral logic of merciful care for vulnerable and dependent persons. Specifically, Aquinas stipulates the moral imperative to counsel and protect human beings who variously and unequally ‘lack the use of reason’ due to an extraordinary injury of the cognitive faculties. In chapter 3 we focus on Augustine’s account of the image of God and the mind (mens); Aquinas’s appropriation and development of Augustine on the activity of the imago trinitatis; Aquinas’s understanding of the rational soul as the substantial form of the body; and the incorruptible aptitude of the rational soul to image God by knowledge and by love. Part 2 (chapters 4 and 5) treats Aquinas’s understanding of the second perfection or orderly operation of the human being, and the effects of original sin upon that activity. The objective is to depict Aquinas’s account of the purpose and perfection of the human being and to do so by showing how he went beyond Aristotle and Augustine. Chapter 4 describes Aquinas’s understanding of the operational limitations unequally experienced by particular human beings as a consequence of original sin. We address, according to Aquinas, how the second perfection of the human being in operation came to be wounded, and we formulate a metaphysical account of evil suffered (or affliction). From that basis, a typological sketch of corporeal infirmity and cognitive impairment on Aquinas’s terms is provided. The purpose of this systematic overview is to reconstruct Aquinas’s theology of disability and cognitive impairment, to show its internal coherence, and to indicate points of significance from the aspect of our creaturely dignity and creaturely destiny. Chapter 5 describes how those who ‘lack the use of reason’ participate in the sacramental life of the Church (principally through Baptism and Eucharist). In particular, we treat Aquinas’s understanding of the condition amentia (‘mindlessness’), where a person ‘lacks the use of reason’ due to a profound and utterly debilitating impairment of particular corporeal and cognitive faculties. We provide an account, on Aquinas’s terms, of the moral implications of a profound cognitive impairment on the order of amentia. Our interest is the way Christians afflicted with amentia can, on Aquinas’s view, participate in the life of the Church and live the virtues. Specifically, just as the acquired virtues dispose and enable a person to act in accordance with the light of natural reason, which is proportionate to human nature; in the light of grace and consequent of baptism, the infused virtues dispose and enable a person to act in a ‘higher manner’ and toward ‘higher ends,’ in relation to a ‘higher nature’—which is our progress toward the perfect participation of the blessed in the divine nature. On Aquinas’s terms, the consummation of grace and infusion of supernatural virtue at baptism can be understood to capacitate someone who completely ‘lacks the use of reason’ with supernatural knowledge and a supernatural principle of self-movement. So capacitated, there is no reason to deny that a person afflicted with an amentia-like condition could be graced to realize a meritorious magnanimity in knowledge and love of God. Likewise, on Aquinas’s terms, there is good reason to believe that in baptism persons with profound and utterly debilitating cognitive impairments are capacitated for Christian friendship—even as they remain incapable of performing the acts ordinarily associated with Christian friendship. That is to say, although profoundly impaired, through baptism a person with an amentia-like condition is capable of the kind of friendship that is only possible for creatures endowed with an immortal and incorruptible rational soul. It is a friendship based on the fellowship of our deepest happiness, which is the consummation of grace; where our creaturely likeness to God according to image (by knowledge and by love) precedes and causes a supernatural likeness that we share as members of the Body of Christ. Beginning with a thorough description of the human being and corporeal infirmity, on Aquinas’s terms, and in light of his main influences, it is possible to reconstruct his account of cognitive impairment as such, its moral implications, and the moral significance of profound bodily affliction in the Christian understanding of the good life. The goal is to bring to light the doctrinal and moral integrity of what Aquinas says about physical disability and cognitive impairment—he says quite a lot—and, subsequently, to make reasonable inferences on those matters where he is silent. Fate is not destiny. Saint Thomas Aquinas helps us recognize our fate—we who are or who will soon become weak, disabled, and cognitively impaired—in the light and the hope of the Divine consummation of nature, grace, and glory. He helps us not only to see but also to recognize that the existence of the mortal rational animal, the image of God, is beautiful. It is the beauty that belongs to the One called Beautiful, the exemplar after whom our likeness is for now but an imperfect shadow. Our infirmities, the evil we suffer, and the afflictions of our mortal wretchedness is our fate; but our fate will be redeemed and made perfect in the light of His glory, through the Beauty of the Cross. [1] For Aquinas, the question of happiness is the principle concern of all morality. To be happy is to live a good life, which is the life of moral virtue. Affirming that basic judgment, Servais Pinckaers, O.P., remarks that “if the idea of happiness is the initial consideration in moral theology, the place of suffering will be obvious, for it is precisely the reverse of happiness. Suffering will then be an element of moral theology from the very start…[the] banishment of the consideration of suffering from ethics is an outgrowth of a rationalistic conception of the human person.” Servais Pinckaers, The Sources of Christian Ethics (Washington, D.C.: Catholic University of America Press, 1995), 25.



Th.D. Dissertation




Romero, Miguel J (2012). St. Thomas Aquinas on Disability & Profound Cognitive Impairment. Dissertation, Duke University. Retrieved from


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