1. Happiness (Utilitarianism): Actions are judged by their ability to maximize overall happiness or minimize suffering (e.g., Bentham, Mill).

2. Duty (Deontology): Morality is based on adherence to universal rules or duties, regardless of consequences (e.g., Kant’s categorical imperative).

3. Fairness/Justice: Moral actions promote equality, fairness, and just distribution of resources (e.g., Rawls’ theory of justice).

4. Virtue (Virtue Ethics): Morality is tied to cultivating virtuous character traits, such as courage, honesty, and compassion (e.g., Aristotle).

5. Rights: Actions are moral if they respect and protect individual rights (e.g., Locke, Nozick).

These principles often overlap or conflict, depending on the context and philosophical perspective.