1. Natural Law

2. Earliest example: Plato

3. Earliest example: Plato
There is objective reality

4. Earliest example: Plato
There is objective reality
We can discover what reality is through rational activity

5. Earliest example: Plato
There is objective reality
We can discover what reality is through rational activity
Right and good are properties discoverable through rational activity

6. Earliest example: Plato
There is objective reality
We can discover what reality is through rational activity
Right and good are properties discoverable through rational activity
A thing’s virtue is understood through its function, which is understood through its nature

7. Plato: human virtue consists in inner harmony; rational self-control

8. Plato: human virtue consists in inner harmony; rational self-control
Wisdom
Courage
Moderation

9. Plato: human virtue consists in inner harmony; rational self-control
Wisdom
Courage
Moderation
= justice; the good life

10. Plato: human virtue consists in inner harmony; rational self-control
Wisdom
Courage
Moderation
= justice; the good life
Moral reality is part of reality

11. Plato: human virtue consists in inner harmony; rational self-control
Wisdom
Courage
Moderation
= justice; the good life
Moral reality is part of reality
Objective
Discoverable by human intellect

12. Plato: human virtue consists in inner harmony; rational self-control
Wisdom
Courage
Moderation
= justice; the good life
Moral reality is part of reality
Objective
Discoverable by human intellect
Laws are attempts to discover objective justice

13. Cicero
Roman thinker; several hundred years after Plato

14. Cicero Roman thinker; several hundred years after Plato
Moral order is a feature of the world

15. Cicero Roman thinker; several hundred years after Plato
Moral order is a feature of the world
Moral duties can be discerned by the intellect

16. Cicero Roman thinker; several hundred years after Plato
Moral order is a feature of the world
Moral duties can be discerned by the intellect
Influence of Plato and Aristotle; Roman law

17. Three things to consider
Is the contemplated act morally right or morally wrong?
Is that act expedient; that is, conducive to comfort and happiness?
What should we do when what seems expedient seems to conflict with what is right?

18. Three things to consider
Is the contemplated act morally right or morally wrong?
Is that act expedient; that is, conducive to comfort and happiness?
What should we do when what seems expedient seems to conflict with what is right?
Cicero: rightly understood, everything that is morally right is expedient, and everything that is expedient is morally right

19. Expedience
Concerned with enjoyment, influence, and wealth

20. Justice is expedient because it is required for social cooperation

21. Justice is expedient because it is required for social cooperation
Kindness and generosity are expedient, but only when exercised within appropriate limits

22. Why morality and expedience don’t conflict
Cicero:
Nothing is so repugnant to Nature as immorality.
Nothing is so in accord with Nature as expediency.
Therefore, expediency and immorality cannot coexist in one and the same object.

23. How do we figure this out?
Four sources of rightness
Wisdom - Virtue concerning matters of truth and knowledge

24. How do we figure this out?
Four sources of rightness
Wisdom - Virtue concerning matters of truth and knowledge
Justice and charity - Virtues concerning the maintenance of society and “common bonds”

25. How do we figure this out?
Four sources of rightness
Wisdom - Virtue concerning matters of truth and knowledge
Justice and charity - Virtues concerning the maintenance of society and “common bonds”
Courage - Virtue concerning greatness of spirit

26. How do we figure this out?
Four sources of rightness
Wisdom - Virtue concerning matters of truth and knowledge
Justice and charity - Virtues concerning the maintenance of society and “common bonds”
Courage - Virtue concerning greatness of spirit
Temperance - Virtue concerning moderation and self-control

27. How do we figure this out?
Four sources of rightness
Wisdom - Virtue concerning matters of truth and knowledge
Justice and charity - Virtues concerning the maintenance of society and “common bonds”
Courage - Virtue concerning greatness of spirit
Temperance - Virtue concerning moderation and self-control
Propriety – includes other things thought to be virtues
Know through wisdom

28. We ought to avoid thinking of morally wrong actions as expedient
We ought to do what the intellect has discerned to be morally right