aquinas' natural law

  • “the first principle of practical reason is…good is to be done and pursued, evil is to be avoided”

  • all humans act towards an end, ultimately the end is Eudaimonia (happiness)

  • eudaimonia is the highest faculty of a person

  • properly moral acts are free acts of rational people

  • eudaimonia can only be found in the ‘ultimate end’

  • the ultimate end cannot be found in this world

  • this world only provides temporary or partial satisfaction

  • the ultimate end can only be found in God

  • the natural light of reason means all human beings seek this end

  • divine help is needed in moral decision making to guide us towards the ultimate end

  • “ultimate and perfect beatitude (happiness) can consist only in the vision of the divine essence, which is the very essence of goodness” » summa theologica

the four tiers of law:

  • the eternal law: the unchanging reason of God (upon which all other laws depend)

    • God is morality

    • morality is not a separate entity

  • the divine law: the commands and teachings of divine revelation eg the Bible

  • the natural law: the perception of the eternal law through the use of human reason

  • the human law: when we apply our knowledge of morality gained from reason and revelation to form the customs and practices of society

the key precepts - the synderesis rule:

  • the key precept: do good, avoid evil

    • natural law is law-like, rooted in human reasoning.

    • divine reason, though incomprehensible, is discernible through human reason.

    • the moral life is lived through reason.

    • natural law is act-based and deontological, oriented toward an ultimate end.

primary precepts

secondary precepts (deduced from primary precepts)

worship God

He is the source of eternal law and has sent this law to humanity

attend mass every Sunday

ordered society

lawful and possible to follow the primary precepts

punish those that bring disorder

reproduce

to ensure that life continues as is God’s intention

forbid contraception

learn

teach people about God, eternal law, natural law, divine law, primary precepts

send missionaries to spread the Word of God

defend innocent life

life is precious above all else

forbid abortion, euthanasia, suicide, etc…

real and apparent goods:

  • aquinas:

    • every human's nature is fundamentally good.

    • fallible humans make mistakes.

    • temptation can distort the perception of what appears good.

    • this distortion hinders correct reasoning and obscures the 'real' good.

    • humans aim to pursue the 'real' good but can make mistakes in doing so

» “No evil can be desirable, either by natural appetite or by conscious will. It is sought indirectly, namely because it is the consequence of some good…a fornicator seeks a pleasure which involves him in moral guilt.”​ ~ aquinas, summa theologica

how do we overcome these apparent goods?

  • aquinas thought that reason identified natural/cardinal virtues:

    • Prudence (cautious)​

    • Temperance (self-restraint)​

    • Fortitude (moral strength)​

    • Justice (fairness/equity)

  • 7 vices/cardinal sins that tempted us to stray from the virtues:

    • Pride (ego)​

    • Avarice (greed for material gain)​

    • Lust (sexual desire)​

    • Envy (desire for something belonging to another)​

    • Gluttony (excessive eating)​

    • Anger (hostility to others)​

    • Sloth (laziness)

  • to pursue natural law we need to:

    • develop the virtues

    • eliminate the vices