⁶ The happiness, according to Jeremy Bentham, include not only happiness of sense and wealth, but also amity, benevolence and skill, etc.⁷ These are similar to Maslow's love and self-actulization.⁸ Bentham pointed out profoundly that “common sense”, “rule of right”, “law of nature”, etc, are all reducible to the principle of utility, asceticism is only a misuse of the principle of utility.⁹ David Hume proved that morality cannot originate from reason, reason ought to be the slave of sensibility.¹⁰ The super-ego, which Sigmund Freud mentioned, is the slave of id, too.

Jacques P. Thiroux distinguished egoism with utili- tarianism. Universal ethical egoism states as its basic principle that everyone should always act in his own self-interest regardless of the interests of others unless their interests also serve his. Utilitarianism try to figure out which act would bring about the greatest amount of good consequences not just for himself or herself, but for everyone involved in the situation. Both egoism and utilitarianism are consequentialism. One of the reasons, which Jacques P. Thiroux and some other philosophers opposed consequentialism, is that benefit is difficult to assess.¹¹ It is difficult indeed, especially when different benefits of a person or of different people are contradictory. But we have to assess no matter how difficult it is, and in fact, everyone is calculating his benefit every day. For example, we always calculate gains and losses again and again when we go shopping, marry, or look for a work. Companies always forecast before investment, governments always assess the result before practise a policy or sign a treaty. There are usually mistakes among these assessments, but people are always learning from mistakes.

Bentham, Hume, Mill, Han Feizi (lived in China more than 2200 years ago), and many other philosophers have implied the principle of utility, but few of them explained the basis of it correctly. Bentham and Mill believed that the principle of utility cannot prove.¹² In fact, this principle is only able to be proved by the knowledge of the essence of life. Adam Smith cited the theory of Zeno, the founder of the Stoical doctrine, to explain the origin of utility principle: Every animal was by nature recommended to its own care, and was endowed with the principle of self-love, that it might endeavor to preserve, not only its existence, but all the different parts of its nature, in the best and most perfect state of which they were capable. ¹³

The principle of egoism of animals leads to the law of jungle. Similarly, the principle of egoism of people also leads to the law of jungle, which is practiced in politics, military, economy, sports and so on, in history and now. Why do not I get my benefit by force, which is often the simplest way, if I can? Why should I care about others and learn to be gentle?

Ⅲ. Definition of Good and Evil

The concept good has two different meanings, one is beneficence opposite evil, another is utility opposite bad or loss. The