The 60-Second Aquinas
Lesson
Natural Law vs. Human Law
November 9, 1998
Aquinas defines law as "a rule and measure of acts, whereby man is induced to act or is restrained from acting" (ST I-II, Q. 90, Art. 1).
The rule and measure of acts defined by natural law is unwritten. Natural law is something internal, tied closely to our conscience. It is our participation in God’s eternal law, and it guides us in making decisions.
Natural law is concerned primarily with universal principles. We inherently know universal principles like "You should not kill others" or "You should treat others fairly." But, it is when we are faced with a specific choice of action that our conscience guided by natural law tells us the correct choice.
Human law, on the other hand, is concerned only with particular situations. Aquinas defines the human law as "particular determinations devised by human reason" (ST I-II, Q. 91, Art. 3).
To drive 35 miles per hour on a specific road might be within the law, but 35 might be an excessive speed in a school zone or dangerously slow on a freeway. Attempting to buy alcohol in one state at the age of 20 might be illegal, but in another state or country, it might be permissible according to the written law.
Explanation of The 60-Second Aquinas Lesson
