Handout: Aquinas and Natural Law Theory
St. Thomas (1225-1274)
Summa Theologia
-
Eternal Law: divine plan used by God to create and rule the world; governs
everything
o This divine plan gives everything a role or purpose (telos)
▪ e.g. eyes designed for seeing; rain falls to nourish plants
-
Natural Law
o Tells us what is right/wrong
o Discerned by human beings using the natural light of reason
▪ We have reason since we’re made in the image of rational God
o Most basic precept of natural law theory is self-evident truth that we
should do good and avoid evil
▪ What is good and what is evil?
• Goodness is in accord with natural inclinations
• Evil is opposed to natural inclinations
o e.g. humans have a basic inclination to preserve life
and avoid death so actions that preserve life are
o right and those that those that do not are wrong
-
Civil (Human) Law
o We create our own laws in order to apply the natural law to the specific
circumstances of our society
-
Two problems with natural law theory
o Conflict with science: science does not explain things in terms of
purposes or values, e.g. rain falls because gravity not to nourish plants
o How do we know what the natural law says? e.g. rational people don’t
always agree about values and even Catholics who subscribe to natural
law do not always agree about everything