St. Thomas Aquinas

Mr. Dunn

Basic facts about Thomistic philosophy

• Integration of Aristotle with Christianity• Natural Theology, which is the use of reason

to articulate truths of revelation (the Bible and the Church)

• Everything is ordered in a hierarchy with God at the top.

• God is that toward which everything and everyone ought to be directed

Aristotle + Christianity = Aquinas

• By the thirteenth century, there was a trend towards focusing on the natural world as opposed to calling it evil as Augustine did.

• The philosophy of Aristotle saw a resurgence.• Aquinas’ goal was to Christianize Aristotle.• Aquinas also wanted to show how reason and

faith can work together to explain our world and to explain how we should live our lives in accordance with our nature.

Form and Essence

• Like Aristotle, Aquinas believed that the form of things are within substances themselves, not in another world. He called these essences (what makes things what they are).

• We can use observation and reason to understand essence. (similar to Aristotle)

Natural theology

• The philosopher uses reason alone.• The theologian accepts revelation (the Bible and the

Church) as authority.– Revealed theology- truths accepted purely on faith (God

sent His only son to save us from sin)– Natural theology- reason can corroborate revelation

(Nothing can exist unless God (the first cause and necessary being) exists)

– When faith can’t be explained by reason, then we simply need to accept them based on faith. Yet, when it’s possible to understand revelation by using reason, we should.

Actuality vs. Potentiality• The being of everything in this world has actuality and

potentiality.• God is the only 100% actual being.

– Everything else has a different degree of actuality. What’s left is potentiality.

– NOTE: Aquinas never used percentages. I’m simply using these to illustrate the concept.

– Humans- 85% actual being/ 15% potential being– House fly- 35% actual being/ 65% potential being

• There is no existence without essence and no essence without existence.

• Therefore, there needs to be an actual being in order for any potential being to exist. Therefore, God exists.

The soul is the essence of…

• One difference between Aristotle and Aquinas– The soul, according to Aristotle, is the form (or the essence)

of the body– The soul, according to Aquinas, is the form (or the essence) of

the person himself or herself.– In other words, Ben Gerke’s soul exists alongside the body to

make Ben who he is (according to Aristotle)– In other words, Ben Gerke’s soul exists alongside Ben Gerke’s

personhood to make Ben who he is (according to Aquinas)• A confusing part of this is that Aquinas believes that a person’s body

is a part of personhood, and the personhood and the body are always united.

Aquinas’ cosmological proofs for the existence of God

• Five proofs for the existence of God• All begin with observations of the natural world• Example- the second proof• Observe that baby chicks come from mother

chickens.• All efficient causes must have a first cause or

else there would be no effects. Therefore, there is a first cause and that first cause is God.

Teleological Morality

• All of Aquinas’ thoughts are teleological, especially his ethics.

• Every action has an end or a purpose (final cause).• All final causes have an ultimate final cause which is

God.• God, as the final causes, bestows meaning on every

action that exists since every action ultimately leads to God. Thus, without God, all actions would be meaningless. Also, human life itself would be meaningless.

Natural Law

• Aquinas defined Natural Law as God’s law applied to human beings.

• God gave human beings freedom; therefore humans are free to obey the natural law or not.

• Going against God also goes against everything it means to exist and everything it means to be a human being.

• In Thomas’ moral philosophy, both reason and Biblical revelation lead to the same conclusion. Thus natural law stems from natural theology.

Scholasticism

• Aquinas’ theology is part of scholasticism, which is the thirteenth century quest to explain Catholic theology through reason.

• This emphasis on observing the natural world began a movement which ironically would eventually reject speculative thinking about God and eternity. This movement flourished during the Renaissance.

• The Renaissance was characterized by a fascination of this world and a disdain for speculative metaphysics.