Aquinas and the Natural Habit of Synderesis: A Response to Celano

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Lisa Holdsworth


Anthony Celano argues that after Thomas Aquinas the flexibility of Aristotle’s ethics gives way to the universal codes of Christian morality. His argument posits that the Schoolmen adopted a line of moral reasoning that follows a Platonic tradition of taking universal moral principles as the basis of moral reasoning. While Thomas does work in a tradition that, resemblant of the Platonic tradition, incorporates inerrant principles of moral reasoning in the habit of synderesis, his understanding of those principles is distinctly Aristotelian in character and thus the flexible moral reasoning of Aristotle’s phronimos is retained. For Thomas synderesis is the first principle of practical reason and is the source rather than the inhibitor of personal and spontaneous moral reasoning. This article will first outline Celano’s position, detail the thought of Thomas’ predecessors, and then show how Thomas employs the principle of synderesis in a distinctly Aristotelian framework.


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How to Cite
Holdsworth, Lisa. 2016. “Aquinas and the Natural Habit of Synderesis: A Response to Celano”. Diametros, no. 47 (March):35-49.
Special Topic - Thomas Aquinas' Theory of Conscience and Contemporary Debates on Conscientious Objection
Author Biography

Lisa Holdsworth, Catholic University of America

Lisa HoldsworthCatholic University of AmericaSchool of Philosophy620 Michigan Avenue Washington, DC 20064 USA 


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