Bumper stickers and ethical systems
When in Rome, do as the Romans do: cultural relativism
Look out for number one: ethical egoism
I couldn't help myself: behaviorism
Survival of the (ethical) fittest: evolutionary ethics
The greatest happiness: utilitarianism
It's your duty: Kantian ethics
Be good: virtue ethics
The moral of the story is ... : narrative ethics
All you need is love: situation ethics
Doing what comes naturally: natural law ethics
God said it, I believe it, that settles it: divine command theory
Unraveling the options.