Belief in the sense intended by the Creed is not an incomplete kind of knowledge, an opinion that subsequently can or should be converted into practical knowledge. It is much rather an essentially different kind of intellectual attitude, which stands alongside practical knowledge as something independent and particular, and cannot be traced back to it or deduced from it… Every man must adopt some kind of attitude to the basic questions, and no man can do this in any other way but that of entertaining belief. There is a realm which allows no other answer but that of entertaining a belief, and no man can completely avoid this realm.
Introduction to Christianity, 40-1
Reflection - We all know what practical knowledge is, right? I know how to: write a blog post, drive a car, bake a cake, play the guitar, read Greek, celebrate Mass according to the Church's rubrics, and so forth. And we all walk through our days doing stuff that we know to do by our practical knowledge.
Ratzinger has often returned in his career to this early insight of his (this book is from the 1960s), that belief is something of a totally different order than practical knowledge. Practically speaking, we know things that are less than us, things we can master (caveat: I don't master the Mass, of course, but I do master the book containing the rubrical instructions and prayers for the Mass!).
But we all live in a world where we rub up against reality we cannot master, reality which is above us, beyond us, bigger than us. Not simply more practical stuff that we just haven't gotten around to learning yet, like quantum physics, but reality 'as a whole' - the underlying and overarching reality behind reality, the purpose, meaning, nature-in-itself of all that is. And individual realities that are by their nature not master-able - love and communion and other people and incidental stuff like that.
This is stuff we can know by practical knowledge, by knowing how to do this or that. This is something we can only engage by an act of faith, whether that is an explicitly religious, Christian faith, or some other kind of faith.
In other words, these immense realities, and reality as such are received by us, not mastered or made by us. To try to live without faith is to condemn ourselves to living in a world in which we are the biggest reality we know. And what a lamentable state of affairs that is.
This is to become less than human. To cut ourselves off from a world we cannot master is to cut ourselves off from every other human being and ultimately from ourselves. As Leonard Cohen sang many years ago, "You lose everything that cannot control/It begins with your family, but soon it comes round to your soul."
To live without faith, without belief, without opening yourself to the world as mystery, the world as gift, the world as awesome marvel, is to live without a soul. And this is to live a sub-human life, ultimately.Without faith, we are less than human, because without faith we are alone in a technological world, a world in which all there is to do is make stuff and master stuff and make more stuff.
We are made to know and to love, to delight and rejoice, to contemplate and to receive. But only faith opens us up to this fullness of life.