Utilitarianism, particularly in its classical form, holds that the morally right action is the one that produces the greatest happiness or well-being for the greatest number of people.

The categorical imperative is a fundamental principle in Kantian ethics that states that an action is morally right if and only if it can be universalized, i.e., if it can be consistently applied to all similar situations without contradiction.

Virtue ethics emphasizes the importance of developing and acting in accordance with virtues, which are considered to be desirable character traits that contribute to eudaimonia (flourishing or well-being).

Existentialism, particularly in its existentialist ethics, emphasizes the importance of individual freedom, responsibility, and authenticity in making moral choices, rather than relying on external moral principles or societal norms.

Ethical egoism is a theory that holds that the morally right action is the one that best promotes the agent's own self-interest.

The social contract theory suggests that individuals enter into an implicit agreement with society, whereby they give up some of their freedoms in exchange for the benefits and protection provided by living in a cooperative and organized community.

Rawlsian Justice, proposed by John Rawls, emphasizes the importance of impartiality and fairness in moral decision-making, particularly in the context of social and political institutions.

Consequentialist ethical theories, such as utilitarianism, focus primarily on the consequences of actions in determining their moral rightness or wrongness.

Kantianism, particularly in its deontological form, emphasizes the importance of following moral rules and principles, regardless of the consequences, as these rules are believed to be universally binding and grounded in reason.

The ethics of care emphasizes the importance of relationships, empathy, and care for others in moral decision-making, rather than relying solely on abstract principles or rules.

Natural Law Theory suggests that there is a universal moral order based on human nature and the natural world, and that moral rightness or wrongness can be determined by examining this natural order.

The ethics of reciprocity emphasizes the importance of treating others as you would like to be treated, promoting fairness and mutual respect in moral interactions.

Negative Utilitarianism focuses on minimizing suffering and harm, rather than maximizing pleasure or happiness, as the primary goal of moral decision-making.

The ethics of sustainability emphasizes the importance of considering the long-term environmental and social consequences of actions, promoting responsible resource use and intergenerational justice.

Libertarianism emphasizes the importance of individual autonomy and the right to make one's own choices, free from external coercion or interference, as long as those choices do not harm others.