ON THE same Wednesday, the day of Dunblane, death also came to the film-maker Krzysztof Kieslowski. They were children; he was a middle- aged man whose country was far from Scotland and who had already lived much of the happiness, sadness and achievement denied to them. But he had already come to my mind that day, before I heard the news of his death on the car radio.

The first film in his Dekalog series is, to me, the most terrible of cinema masterpieces. The series is a meditation on the Ten Commandments, the words on which the Judaeo-Christian tradition rests.

A man who has a small son is entranced with the power and authority of his computer. To demonstrate that power, he calculates the thickness of the ice on the pond and demonstrates that it will bear the weight of a child. But the child falls through the ice and drowns. Then the computer, untouched, begins to write. God has acted to subvert the laws of science, to remind the bereaved father of the First Commandment: "I am the Lord thy God, which have brought thee out of the land of Egypt and out of the house of bondage. Thou shalt have no other gods before me."

What kind of God takes the life of an innocent child, an only son, merely to show his own power and punish a mild idolatry? This is an unbearable thought to believers. But, although I am an agnostic, my own unbelief begins to tremble on its foundations when I remember Kieslowski's film, as I did on the day of Dunblane. Clergymen would prefer their God to be responsible only for what is good. But what sort of God would he be if he were not present in evil? My terror is of finding him most intensely there as the ice breaks under the child, or in the blackness of the gas chambers, or in the gym of Dunblane Primary. Receiving those Commandments, Moses had to "draw near unto the thick darkness where God was". The Scottish poet Hugh MacDiarmid, though contemptuous of religion, once wrote of "the pitch-darkness o' His will".

This is a way of warning that awful events are not meaningless because we cannot read their meaning - or cannot bear the possibility that they might have a meaning. It is true enough that busy indignation about gun laws and school security gates is a completely inadequate response to what happened to Dunblane's children, and - by the way - even the journalists who write those articles know that very well. At the same time, this was not a random event. Perhaps nobody had a serious chance of predicting how Thomas Hamilton would finally solve his own jigsaw puzzle, when on Wednesday 13 March he found the way to fit together his multiple obsessions with children, authority and guns. But it did not happen by chance.

My colleague Polly Toynbee, speaking on Radio 4's Moral Maze, said that Dunblane was like a meteorite falling out of the sky: nothing could be read into it. I know what she means, and yet the sky itself is not a blank but a background which slowly changes. Hamilton's crime has characteristics and came from somewhere. For example, it clearly belongs in the category of "Me Massacres" - indiscriminate slaughters intended to draw attention to the slaughterer. "Me Massacres" are a fairly recent fashion, and not just because modern weapons make them easier; any aggrieved serf could have locked a church and burned its occupants. They seem to have begun about 50 years ago or less, in the United States. We have to discover why.

That does not answer the larger "Why?" Nobody is in a position to answer that. But everyone who shared in sympathy the smallness, weakness and terror of those children was also, for an instant, aware of that thick darkness in which something seems to move and watch. As a German poet wrote, "I am as big as God - He is as small as me".