SPROUL: The double truth theory basically said this: Something can be true
in philosophy and false in religion at the same time. Or it can be true by faith but false
in science at the same time. Now, let’s translate that idea to contemporary categories. We see the
raging controversy that goes on about human origins. Are we as human beings the product
of a purposive act of divine creation, or are we merely fortuitous cosmic accidents, grown-up germs
that have spontaneously come out of a chance collision of atoms, and so on?
Now, obviously we cannot both be purposefully created by a self-existent, eternal God and at the same
time be cosmic accidents. Those two concepts cannot be reconciled. But a double-truth thinker
would say this: “I’m a religious person, but I’m also a scientist. So, on Mondays, Wednesdays,
and Fridays, I will believe in creation, and on Tuesdays, Thursdays, and Saturdays,
I will believe in mass as a cosmic accident. And on Sunday, I’ll rest from the controversy.” Do you
see what’s going on here? It is a separation or a disjunction between faith and reason,
between philosophy and religion, between theology and science, where the two don’t meet or ever
overlap. Now, it’s precisely against that kind of thinking that Saint Thomas Aquinas—who had
been the illustrious student of Albert the Great, and who had been called by his student classmates
while he was in school “the dumb ox of Aquino,” to which Albert the Great replied, “This dumb
ox is going to astonish the world with his brilliance.” But in any case, it was against this
kind of thinking that Aquinas was responding. He realized that if you had that kind of disjunction
between faith and reason, an antithesis between science and religion, you would end up as an
intellectual schizophrenic, and it would make truth impossible to reconcile. And so, he said
that there are certain truths that we learn from nature and other truths that we learn from grace.
What he means by that is something like this: If you study nature, you can learn
something about the circulatory system of the human body. But you can read the Bible
all you want, and the Bible will not reveal to you the intricacies of the circulatory system
of the human body or the molecular structure of a leaf. You have to apply natural science and
empirical investigation to discover that sort of thing. So, you get certain truths—truths
that don’t contradict the Scriptures or contradict special revelation—but
you don’t find that content in the Bible.
You find other truths, according to Aquinas, that are revealed to us only in the Bible,
that you can’t discover with the microscope or with a telescope. For example,
God’s plan of salvation—you can’t study that in a laboratory. You get that through the revelation of
Scripture. So, you have two sources of truth: grace and nature.