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6 - St. Thomas Aquinas on Conscience

from Part II - Conscience According to Major Figures and Traditions

Published online by Cambridge University Press:  12 June 2021

Jeffrey B. Hammond
Faulkner University
Helen M. Alvare
George Mason University, Virginia
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Cajetan Cuddy looks at conscience through the thought of St. Thomas Aquinas. Conscience is an act of ordering knowledge – some universal and some particular – to an act, whether past, present, or future. Conscience directs future acts, and regarding past acts, can accuse or excuse. Aquinas compares conscience and synderesis – the person’s inclination shaping her understanding. Synderesis turns human nature to good and objects to evil. It gives awareness of the principles of morality to be applied to actions. Synderesis concerns knowing the principles applicable to all actions, and conscience applies knowledge to a specific act. Thus, conscience comes from synderesis. But conscience has limits and can be wrong and need correction. A mistaken conscience does not stop a person’s orientation to the truth, and error can be fixed. Conscience and God’s law both bind for Aquinas, not because conscience is perfect or reason is independent of the law, but because conscience mediates God’s norms to humans doing a particular action. This is done through the application of synderesis, which is always ordered to moral truth, meaning to God.

Christianity and the Laws of Conscience
An Introduction
, pp. 112 - 131
Publisher: Cambridge University Press
Print publication year: 2021

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