Thomas Aquinas and Natural Law Introduction

Aquinas on Natural Law: Basic Ideas

Fundamental Problem: What are the minimal moral or ethical expectations that hold for all people, all the time?

Complication: If the the answer is derived from our religious beliefs, we cannot expect people with a different religion to uphold the same standards.

Solution: We must distinguish divine law from natural law. Natural law is the subset of God's law that is available to any rational person, and therefore it provides a moral standard that can be applied to everyone.

Divine law (known through religious revelation) provides our ultimate PURPOSE or END in life: that purpose is knowing God (knowing God forever, in the afterlife, is our ultimate end).

We also have some non-religious ends (secular purposes) governing our earthly life. These ends are the purposes that we naturally have because of the kind of creature that we are. These ends are our natural ends. The rules we can rationally discover concerning these ends are natural laws.

THE BASIC STANDARD OF MORALITY for all persons, at all times, is determined by natural law. To the degree that they are relevant to any action we take, we must pursue our natural ends. We must not do anything that is intended to prevent any of our natural ends.

What are our natural ends? We can decide this by looking at our natural inclinations. (We all have the SAME natural inclinations. These are the ones we have because we are members of the same species. Inclinations which are not common to the species do not provide moral guidance.)

FIRST NATURAL INCLINATION: Self-preservation

SECOND NATURAL INCLINATION: Reproduction, and care of offspring

THIRD NATURAL INCLINATION: Use of reason to organize our lives

The first has priority over the others and the second has priority over the third; a good life promotes all three.

Moral actions promote our natural ends; immoral actions are those that directly frustrate those ends; complicated case is an action that both promotes and frustrates natural ends.