Generous and humane is he who sympathizes with his fellow-men with his sincere heart.  Veracity, chastity, filial piety, loyalty, righteousness, generosity, humanity, and what not-all-this is no other than Buddha-nature applied to various relationships of human brotherhood.  This is the common source, ever fresh and inexhaustible, of morality that fosters and furthers the interests of all.  To-ju[FN#170] expresses the similar idea as follows: 

“There exists the Inexhaustible Source (of morality) within me. 
It is an invaluable treasure. 
It is called Bright Nature of man. 
It is peerless and surpasses all jewels. 
The aim of learning is to bring out this Bright Nature. 
This is the best thing in the world. 
Real happiness can only be secured by it.”

Thus, in the first place, moral conduct, which is nothing but the expression of Buddha-nature in action, implies the assertion of self and the furtherance of one’s interests.  On this point is based the half-truth of the Egoistic theory.  Secondly, it is invariably accompanied by a feeling of pleasure or satisfaction when it fulfils its end.  This accidental concomitance is mistaken for its essence by superficial observers who adhere to the Hedonistic theory.  Thirdly, it conduces to the furtherance of the material and spiritual interests of man, and it led the Utilitarians to the confusion of the result with the cause of morality.  Fourthly, it involves the control or sacrifice of the lower and ignoble self of an individual in order to realize his higher and nobler self.  This gave rise to the half-truth of the Ascetic theory of morality.

[FN#170] To-ju Naka-e (died A.D. 1649), the founder of the Japanese Wang School of Confucianism, known as the Sage of Omi.

15.  The Parable of a Drunkard.

Now the question arises, If all human beings are endowed with Buddha-nature, why have they not come naturally to be Enlightened?  To answer this question, the Indian Mahayanists[FN#171] told the parable of a drunkard who forgets the precious gems put in his own pocket by one of his friends.  The man is drunk with the poisonous liquor of selfishness, led astray by the alluring sight of the sensual objects, and goes mad with anger, lust, and folly.  Thus he is in a state of moral poverty, entirely forgetting the precious gem of Buddha-nature within him.  To be in an honourable position in society as the owner of that valuable property, he must first get rid himself of the influence of the liquor of self, and detach himself from sensual objects, gain control over his passion, restore peace and sincerity to his mind, and illumine his whole existence by his inborn divine light.  Otherwise he has to remain in the same plight to all eternity.

[FN#171] Mahaparinirvana-sutra.