Natural Law and Thomas AquinasQUESTION: Natural Law and Thomas Aquinas
Thomas Aquinas (1225—1274) returns to the view that natural law is an independent reality within a system of human reason approaching (but never fully comprehending) God’s eternal law (and thus needing supplementation by God’s divine law).
Natural Law in Summa Theologica
In Summa Theologica, Aquinas identifies four types of law: (1) eternal; (2) natural; (3) human; and (4) divine.
The eternal law is the ideal type and order of the universe (kosmos) pre-existing in the mind of God (Logos).
The natural law is “the rational creature’s participation in the eternal law.”
"It is evident that all things partake somewhat of the eternal law, in so far as, namely, from its being imprinted on them... Wherefore it (human nature) has a share of the Eternal Reason, whereby it has a natural inclination to its proper act and end: and this participation of the eternal law in the rational creature is called the natural law."
The divine law refers to Special Revelation -- the will of God as revealed in the Scriptures of the Old and New Testaments. This law was necessary for four reasons: (1) humans need explicit divine guidance on how to perform proper acts; (2) uncertainty of human judgment needs a check; (3) humans need divine insight on issues on which they are not competent to judge; and (4) it proves that God will punish some deeds that even go beyond the ability of human law to punish.
-- From Part I (of the Second Part) of Summa Theologica.