Words cannot fully express the horror and revulsion felt around the world wherever people have heard of this week's mindless slaughter of young school children in Scotland.
The mourning is widespread because decent people everywhere have been wounded by the bullets fired by a local man who burst into a school gymnasium in Dunblane and shot 16 kindergarten students and their teacher to death before killing himself.This vile episode does more than just expose a dark side of human nature - a side in which real or imagined grievances can, if unchecked, become lethal to the innocent as well as to those who can't or won't control themselves.
It is also a reminder of our common vulnerability and our common impotence in the face of the irrational.
What parent does not tremble at the knowledge that if such a tragedy can happen in a calm and quiet place as a small town at the gateway to the Scottish Highlands, it can be repeated on various scales elsewhere?
Likewise, who does not regret the inadequate ability of science and the law to detect and contain incipient madness before the potentially violent do serious harm to others and themselves?
Tragedy can serve a sad but useful purpose if mankind learns from it. But the lessons of this week's massacre are few and not particularly encouraging.
Since the killer was a gun lover who carried out the slaughter with four pistols, some may be inclined to see this episode as a strong argument for gun control. But Scotland already has much tougher gun restrictions than there are in the United States or even in much of Europe.
And since the killer was suspected of being addicted to pornography, some may understandably see this tragedy as a strong argument for tougher restrictions on the manufacture and sale of such licentious materials. But the killer is said to have made his own smut by photographing young children.
Even so, the tragedy in Dunblane remains a clear warning of the possible results of pornography, whose addicts tend to look on other people as mere instruments for their personal gratification.
If there is a bright spot among all the horror, it was provided by the slain teacher, whose body looked as though she had been trying to shield the children from the bullets.
May the nobility and self-sacrifice of that heroine be remembered long after the widespread pain from the slaughter in Dunblane has subsided.