God is thus seen more or less as the guarantor of the rationality of human reason

I have decided to give the next section of Hans Kung's argument about the benefits that come with choosing to believe in God and the deficiencies of the choice to refuse to believe in God.  I think what Kung said is a good answer to the demand for a proof of God's existence because it demonstrates that atheism undermines any confidence anyone should have in the very reality such a proof would need to take for granted.  I don't expect most of the atheists one encounters, the kinds who demand such proofs will begin to understand the issues and, so arguments, they're a pretty stupid bunch and aren't interested in intellectual engagement.  That being one of the characteristics of such atheism is one of the surprises of my engagement with atheism. 

One of Kung's greatest contributions is in how he has taken not only a comprehensive view of the rational arguments in relation to choosing to believe in God into his discourse - especially in relation to having a trust in reason and even basic human perception of reality -  it is especially in his inclusion of the experience of choosing to believe in God in all of its continued questioning and testing.  The last part of this section is a virtuoso performance in that regard.

Belief in God rationally justified

After all this, it is obvious that there can be no question of a stalemate, of remaining undecided between belief in God and atheism.  It is clear, then, that man is not indifferent in regard to the choice between atheism and belief in God.  He is handicapped from the start.  Essentially he would like to understand the world and himself, to respond to the uncertainty of reality, to perceive the condition for the possibility of uncertain reality, he would like to know of a primary ground, a deepest support and an ultimate goal of reality;  he would like to know the primal source, primal meaning and primal value.  Here are the roots of religion as a primordial fact. 

Yet here, too, man remains free - within limits.  He can say "No."  He can adopt a skeptical attitude and ignore or even stifle any dawning confidence in an ultimate ground, support or goal;  he can, perhaps utterly honestly and truthfully, declare his inability to know (agnosticism with a tendency to atheism) or he can assert a complete hollowness, a groundlessness and aimlessness of the reality that is uncertain anyway (atheism with a tendency to nihilism).  

As with fundamental trust, so, too, here, without preparedness there is no understanding, without open-mindedness no reception.   And even if I affirm God, denial of him remains a continual temptation. 

But like fundamental trust, so, too, trust in God is by no means irrational.  If I do not close my mind to reality but remain open to it, if I do not try to get away from the very last and very first ground, support and goal of reality, but dare to apply myself and give myself up to it, then I know, not indeed before, not yet only afterward, but by the very fact of doing this, that I am doing the right thing, and even what is absolutely the most reasonable thing.  For what cannot be proved in advance I experience in the accomplishment, in the very act of acknowledging what I perceive.  Reality can manifest itself in its proper depth;  its primary ground, deepest support, ultimate goal, its primal source, primal meaning, primal value, are laid open to me as soon as I lay myself open.  At the same time, in all the uncertainty, I experience a radical reasonableness of my own reason.  Fundamental trust in reason is therefore not irrational.  It is rationally justified.  The last and first reality,  God is thus seen more or less as the guarantor of the rationality of human reason. 

If man, by believing in God, is doing what is absolutely the most reasonable thing, what kind of rationality is involved here?  This rationality is similar to that of fundamental trust. 

-  It is not an outward rationality, which could not produce an assured security.  God's existence is not first proved or demonstrated by reason and then believed, thus guaranteeing the rationality of belief in God.  There is not first a rational knowledge and then confident acknowledgement of God.  The hidden reality of God is not forced on reason.

-  It is an inward rationality,  which can offer a fundamental certainty.  In the accomplishment, by the "practice," of boldly trusting in God's reality, despite all temptations to doubt, man experiences the reasonableness of his trust, based on it as on an ultimate identity, meaningfulness and value of reality, on its primal ground, primal meaning, primal value. 

Has not the connection between fundamental trust and belief in God now become obvious?   From the material standpoint, fundamental trust is related to reality as such (and to my own existence), while trust in God is related to the primal ground, primal support, and primal goal of reality.   Nevertheless, from the formal standpoint, fundamental trust and trust in God display an analogous structure that has its roots in the material connection (despite all the differences) of fundamental trust and trust in God.  For, like fundamental trust, belief in God, too is

- a matter not only of human reason but of the whole concrete, living man, with mind and body, reason and instinct, in his quite particular historical situation, in his dependence on traditions, authorities, habits of thought, scales of values, with his interests and in his social involvement.  Man cannot talk of this "matter" and at the same time keep out of the "matter";

- therefore superrational:  as there is no logically conclusive proof for the reality of reality, neither is there one for the reality of God.  The proof of God is no more logically conclusive than is love.  The relationship to 
God is one of trust;

- but not irrational: there is a reflection on the reality of God emerging from human experience and calling for man's free decision.  Belief in God can be justified in the face of a rational critique.  It has a basis in the experience of uncertain reality itself, which raises the first and last questions about the condition of its possibility;

- not, then, a blind decision, devoid of reality, but one that is grounded in the related to reality and rationally justified in concrete life.  Its relevance to both existential needs and social conditions becomes apparent from the reality of the world and of man;

- realized in a concrete relationship with our fellow men;  without the experience of being accepted by men, it seems difficult to experience acceptance by God;

- not grasped once and for all, but constantly to be freshly realized:  belief in God is not secured against atheism unassailably and immune from crises by rational arguments.  Belief in God is continually threatened and  - under pressure of doubts - must constantly be realized, upheld, lived, regained in a new decision:  even in regard to God himself, man remains an insoluble conflict between trust and mistrust, belief and unbelief.  But throughout all doubts and precisely in this way, the affirmation of God is proved in fidelity to the decision once made, it becomes a tried and tested belief in God.