Ancestral spirits are regarded as beneficent beings who never causelessly use their mysterious powers to injure the living; but if their descendants lead evil lives, or neglect the family sacrifices, or treat the sacred rules of filial piety with contempt, then the spirits will in all probability exercise the parental prerogatives of punishment. The power of a father in China to castigate his son is theoretically as absolute in the case of a grown-up son as in the case of one who is still a child: similarly it is supposed that the father does not, by the mere accident of death, divest himself of his patriarchal rights of administering justice and inflicting punishment on his sons and grandsons. Provided a man carefully observes the traditional ceremonies and leads a good life according to the accepted ethics of his race, he knows that he has nothing to fear from the souls of his ancestors. But there are in China various classes of ghosts who are supposed to be highly malevolent and to constitute no small danger to the community. There are, for example, the ghosts whose tempers have been soured by calamity and misfortune; those whose bodies have not been buried; those who were drowned at sea; those who ended their mortal lives by unjustifiable suicide and haunt the place where they died until they can, by ghostly suggestions, prevail on one of their earthly neighbours to follow their example;[227] those who died before accomplishing a vow or completing an act of vengeance: these and many others are ghosts or evil spirits which the wise man who walks warily through life will do his best to avoid. The curious and cruel superstition which sometimes prevents a Chinese from helping a drowning comrade even when he could save the man without danger to himself has its origin in a fear that he will incur the deadly hostility of a spirit that demands the toll of a human life. It is even thought in some places that by saving your friend you may be condemning yourself to be his future substitute. This superstition has existed in many parts of the world--from Ireland to the Solomon Islands.[228] It need hardly be said that educated opinion in China is altogether opposed to the heartless abandonment of drowning men: the superstition is an active force only in a few localities, and only to a minute extent, if at all, may it be said to exist in Weihaiwei.