These four theories were put forward by four western scholars: Aristotle, Kant, Mill and Rawls.
Virtue theory
Virtue ethics was born in ancient Greece and can be traced back to Plato and Aristotle. Its central words are virtue and emphasizing existence rather than action.
Plato once argued that knowledge is a virtue. He looked at the world from a dualistic point of view, and divided it into the conceptual world and the phenomenal world. He also believes that the original clean and innocent soul of human beings is polluted by the bloody experience of birth, and the only way to return to the conceptual world is to think philosophically and learn knowledge constantly.
Aristotle is a student of Plato, and what he is best at is philosophical thinking. Aristotle's virtue ethics is based on teleology.
Obligation theory
After the value subversion of modern enlightenment, the certainty of moral responsibility is mainly based on several basic reasons, such as command theory, utilitarianism, contract theory and virtue theory.
Kant's deontological thought of absolute command provides a shocking and admirable way for the stipulation of obligation. This is a universally valid moral requirement. Kant reasonably revealed that a moral obligation of goodness must be universal.
Consequentialist ethics
Utilitarianism, namely utilitarianism, is a theory in moral philosophy (ethics). Advocate the pursuit of "the greatest happiness." The main philosophers are john stuart Mill and Jeremy Bentham. Utilitarianism, also known as "utilitarianism" and "utilitarianism", usually refers to an ethical theory based on actual efficacy or interests.
Justice ethics
A Theory of Justice is a landmark work of john rawls's political philosophy and ethics. First edition 197 1, revised edition 1975 and 1999. In this book, Rawls tries to solve the problem of distributive justice through the derivation of social contract.
The resulting theory is called "justice as fairness" (justice embodied by fairness, or just a little fairness), and his two principles of justice are derived from this theory: freedom principle and equality principle. The principle of equality is embodied in the principle of equal opportunity and the principle of difference.