Natural Law

Doctrine of Double Effect

action with good + bad effects permissible if bad unintended

Primary Precepts

five fundamental rules of natural law theory, developed by Thomas Aquinas, which guide human behavior

Secondary Precepts

practical rules derived from primary precepts → culturally adaptable

Apparent Goods

items that ought to be desired regardless if we really do; Examples are sweets, good music, and fine wine)

Real Goods

actions fulfilling human nature + achieving telos → true moral guidance like (food, shelter, health, wealth, pleasure, knowledge, and liberty, friends, and civil peace)

Telos

ultimate human purpose → flourishing achieved through reason

Interior Acts

intention/motivation of action → morality judged by intent

Exterior Acts

physical act itself → judged with interior acts

Natural Law

humans participate in Eternal Law via reason → guides towards telos

Eternal Law

God’s divine plan → humans participate through reason

Human Reason

tool for discerning moral truths → allows participation in Eternal Law

Synderesis

innate habit of understanding basic moral principles or doing good → guides reasoning

Eudaimonia

human flourishing → virtuous life in accordance with reason

Why is rigidity a weakness?

inflexible in modern ethical dilemmas e.g. self defence

Why is religious bias a weakness?

relies heavily on God-centered worldview → limits universality

Why is cultural relativism a weakness?

secondary precepts conflict across societies → questions universality

Why is universal moral guidance an advantage?

provides objective standards → supports reasoned ethics

Why is human rights an advantage?

underpins justice + rights → rational foundation for laws

Double Effect example

high-dose pain relief may shorten life → permissible if intention is to relieve pain

Primary Precepts mnemonic : POWER

Preservation of Life Ordered Society Worship God Education Reproduction

Apparent vs Real Goods example

fame mistaken for happiness (apparent) vs cultivating virtue + knowledge (real)

Interior vs Exterior Acts example

charity with love (interior) vs charity for recognition (exterior)

Natural Law vs Legal Positivism

morality is objective + reason-based

For Natural Law

reason + morality universal → basis for ethics beyond legislation

Against Natural Law

morality culturally relative → claims of universal goods may be rigid/outdated

Church support

“Natural Law is written in the heart of every man” → conscience + moral guidance

How does Aquinas support Natural Law?

“Good is to be done and pursued

How does the Church support Natural Law?

“Natural Law is written in the heart of every man”

How does Mackie critique Natural Law?

“Morality is simply a human invention”

How does Hume critique Natural Law?

“There is no ultimate purpose to nature”

Double Effect criteria

act must be good/neutral

Natural Law in bioethics

guides euthanasia + abortion using primary precepts + double effect