Aquinas, ius gentium, and the Decretists

Area of Science:

• Legal History
• Philosophy of Law
• Canon Law

Background:

• Thomas Aquinas's concept of ius gentium originated from Gratian's canon law.
• Gratian's work incorporated ideas from Isidore of Seville.
• Aquinas's ius gentium diverged from Gratian's, heavily influenced by Roman law interpretations.

Purpose of the Study:

• To analyze the decretists' reinterpretation of ius gentium.
• To understand how this reinterpretation influenced Aquinas's legal thought.
• To trace the evolution of ius gentium from canon law to Roman law influence.

Main Methods:

• Historical analysis of canon law texts.
• Examination of Gratian's Decretum and decretist commentaries.
• Comparative study of Gratian's and Aquinas's conceptions of ius gentium.

Main Results:

• The decretists developed a conception of ius gentium distinct from Gratian's.
• This reinterpretation incorporated civilian interpretations of Roman law.
• The decretists' work created a foundation for Aquinas's integration of Roman law into ius gentium.

Conclusions:

• The decretists played a crucial role in shaping Aquinas's understanding of ius gentium.
• Early canon law interpretation facilitated the assimilation of Roman law principles.
• This evolution highlights the dynamic nature of legal concepts in medieval thought.