Buddhist ethics are not arbitrary standards invented by man for his own practical and useful purpose. Nor are they arbitrarily imposed from without. Man-made laws and social customs do not form the basis of Buddhist ethics. For example, the styles of dress that are suitable for one climate, period or civilization may be considered indecent in another; but this is entirely a matter of social custom and does not in any way involve ethical considerations. Yet the artificialities of social conventions are continually confused with ethical principles that are valid and unchanging.