More than a crisis of faith, what we have is a crisis of reason, an Italian intellectual, Vittorio Messori, once said.
That is the same point Ratzinger stresses when he said: "beyond all particular questions, the real problem lies in the question of truth."
Of course, if we cannot know the truth, then we cannot know God: we can all become agnostics, and be comfortably righteous. We cannot know that God loves us: it would make no sense to preach Christianity. It won't make a dent!
Remember also that we should not even make an act of faith, if our reason tells us not to do so. It would be immoral to believe if our conscience, no matter how absurdly, tells us not to, said Thomas Aquinas.
Thus, Benedict XVI goes through lengths to disentangle the root of this crisis and show its pernicious effects on our lives. This he does with great analytical skill in his book Truth and Tolerance:
Any thinking that tries to look at reason in itself or to see it as preceding the present world, is contrary to the discipline of the scientific method and is therefore utterly rejected as being prescientific... Within the specific path followed by natural science, this limitation is necessary and right.
If, however, it is declared to be the absolute and unsurpassable form of human thought, then the basis of science itself becomes contradictory; for it is both proclaiming and denying the power of reason.
But above all, a self-limiting reason of that kind is an amputated reason. If man cannot use his reason to ask about the essential things in his life, where he comes from and where he is going... but has to leave these decisive questions to feelings, divorced from reason, then he is not elevating reason but dishonoring it.
The disintegration of man, thus brought about, results equally in a pathological form of religion and a pathological form of science. It is obvious today that with the detachment of religion from its responsibility to reason, pathological forms of religion are constantly increasing.
But when we think of scientific projects that set no real value on man, such as cloning... or ...produce ever more frightful means for the destruction of men and of the world, then it is obvious that there is such a thing as science that has taken a pathological form.