Ontology and Ethics in Thomas Aquinas
This article explains how Aquinas understood: a) apprehension of the first intellectual concepts: ens, verum et bonum simpliciter (Ens is understood metaphysically as composed of human nature and the act of being, ordered according to the bonum); b) establishment of the first and the second practical commandments in a genuinely human or rational person; c) ethics and natural law as essentially derived from ontology. Therefore, natural law only makes sense from a metaphysical point of view, not merely a physical or material one.
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