IN 1864 Pope Pius IX published his astonishing Syllabus of Errors, which denounced freedom of speech, freedom of religion, and "the fatuous notion...that the Roman pontiff can be or should be reconciled to liberalism, progress, and modern civilization." Pius meant that the Church should stay away from any political ideologies, conservative or liberal. Nevertheless, the Syllabus became a sign that the Catholic Church was basically a repressive institution, allied with the forces of reaction.

The Church has never really been able to overcome this charge. The Vatican often scolds right-wing extremism but always seems to go after the left with a vengeance. Pius XII denounced Nazism but excommunicated all Catholic Communists. John Paul II upbraids the dictators of Brazil and the Philippines for their unfeeling attitude toward the poor but warns that nothing can be achieved through revolution or "the lie that is Marxism." At the same time, the Protestant fundamentalist penchant for ultraconservative politics sends frightened liberals scurrying away toward skepticism. Liberalism and Christianity, it seems, have become opposing forces.

Hans Kung has taken it upon himself to change this. Professor of Catholic theology at the University of Tubingen in West Germany, Kung wants to convince us that belief in the Christian God is not inconsistent with progress and modern civilization, to which, unlike Pius IX, we have reconciled ourselves:

Today there is no necessity to be against God because we are for geocentrism and evolution, for democracy and science, for liberality and socialism. No, we can be forthrightly for true freedom, equality, and fraternity...and still believe in God.

Thus begins Kung's eight-hundred-page descent into philosophical, anti-Christian hell, down through the depths of skepticism, Deism, atheism, and finally "nihilism," which Kung defines as the denial of all reality. He burns to prove that it is "rational" to believe in an ultimate reality, and that this reality must be the Christian God. Kung lives in the shadow of Thomas Aquinas, who believed that science and religion did not clash because some things could be proved by science, while others simply had to be believed through faith. Kung revises Aquinas, redrawing the boundary between faith and reason. He declares, once and for all, that it is "rational" to believe in God.

KUNG BEGINS his argument by dismissing every serious competing strain in Western thought to Christianity as sophistry. Sometimes his arguments are effective, particularly his critiques of Descartes and Wittgenstein. But eventually he buries the reader beneath a mound of philosophical jargon. As Kung's arguments become more and more complex, the philosophical debris grows to such heights that one cannot help laughing at serious remarks such as, "Obviously, Kierkegaard did not know Pascal's work firsthand; he quotes him only once, and then indirectly, through Feuerbach." Obviously.

But Kung should not be condemned for the sin of inarticulateness. He disposes of Descartes, Hegel, Marx and others with remarkable self-assurance. Finally he comes face to face with his arch-villain, the Great Satan of Kung's world, Nietzsche, Nietzsche, the apostle of nihilism, stands for everything Kung fears: God is dead, there is no reality, everything is meaningless. Far from believing Kung's favorite quote of Einstein's, "God does not play dice," Nietzsche says, there is no God, there are no dice, there isn't even a game.

Kung feels he can refute Nietzsche by proving it is "rational" to believe in reality. He doesn't do it very well. True, he points out that no one can prove reality doesn't exist. Equally true, however, no one can prove it does. So belief in reality must remain just that--belief.

KUNG FAILS even more embarrassingly in proving that this reality, if it does exist, must be the Christian God. He discusses Eastern philosophies and religions as little as possible, and never mentions Islam at all. He contends that he has no intention of supporting "a God whose arrogant dominion is upheld by an exclusive missionary appeal, contemptuous of freedom." In other words, if the Catholic Church wants to gain converts in the Third World it can't trample on Asian and African ways of thought. But Kung has no choice but to be exclusive and missionary in approach; he insists that all religions are not equally true:

But anyone who knows the concrete reality of the Hindu religion--the disastrous consequences of the cult of the cow, advocated even by Gandhi, of the caste system impossible to break down by any legislation, of the shocking superstition and so on--cannot regard things as equal, and it may perhaps dawn upon him up to a point what Christian faith can mean for men by way of enlightenment and liberation.

Can Kung honestly believe that by showing us what he arrogantly considers the "disastrous consequences" of other religions, he will convince us of the righteous claim of the Christian God? Are the consequences of the cult of the cow any more disastrous than the consequences of Christian Crusader zeal? This can hardly be a "rational" proof for the existence of God.

Despite all of the objections that have been raised against him, Kung has remained a staunch defender of Christianity. The Church, however, does not think much of his approach. The Vatican's Holy Office has declared Kung a heretic and has forbidden him from teaching Catholic theology, ostensibly for his questioning of the infallibility of the Church. Indeed, in Does God Exist? Kung questions and then denounces the Holy Office, the Index of Forbidden Books, the Immaculate Conception, papal infallibility, and Paul VI's condemnation of birth control and homosexuality. He belongs to the liberal Catholic tradition that Plus IX tried to crush with his Syllabus. These are the liberals who believe the Vatican should shed its "ancient and mediaeval world-view," in Kung's words, and compromise with modernism in order to keep more sheep in the fold.

So the Church, claiming that its teachings cannot be altered to satisfy the whims of any one generation, has lost the services of its great apologist. It may not have had any choice. For Kung writes that one does not have to believe all that the Church teaches to be a good Catholic. But where does one draw the line? If Church pronouncements are not sacred, what about the Bible? Kung also dispenses with Adam and Eve, the parting of the Red Sea, the miracle of the loaves and the fishes, and the acts of the apostles. But if all of these can be explained away because they are not "rational," what about the central miracle of Christianity, God becoming a man in Christ? Is it rational to believe that Christ was divine? Kung seems to have doubts:

Against all pious attempts at deification, I maintain that Jesus was Son of God, and with all the consequences, was wholly and entirely man.

But if it is not rational to believe in Christ, we must come back to the question Kung raises but never answers: is it rational to believe that God exists?