I'm afraid your post shows your ignorance of the theological position that at the Fall, Adam's/a human's ability to reason also fell along with the human nature, and thus was unable to discover The God's Truth--including His Pre-Creation Existence--by reason alone, a facility apart from the disclosures of His Special Revelation.
Romanism was falling badly as a force for good until Thomas Aquinas took opposition to the idea that the ability of a man or mankind in general to reason correctly was lost, and instead proposed that the ability to come to unarguable conclusion as to The God's Existence had not been lost, and that the exercise of reason wold restore the Roman Church's claimed Holy Eminence that had somehow gone missing.
And so Romanism has swallowed that Aquinian approach hook, line, and sinker, and has proceeded on that theme ever since, particularly in the Jesuit manifestation. And because of it, found themselves oppositionally rebellious to the better theology of the Gospel of Faith Alone in the Incarnated, Specially Revealed Word of God Alone, through His Grace Alone, received by the preaching of His Written Word Alone, to save and reconcile a human to fellowship with His Father, and to be made judicially guiltless by that complete unreserved irreversible child-like trust in Jesus Messiah as Everlasting Owner, Lord, and Proprietor of that reconciled human, sanctified through progressive control of the Indwelling Holy Spirit to and through suppression and physical death of the old nature.
Perhaps through immersion in the Holy Word, and change by faith obtained from it, Hans Kung had become yet another rejector of the Aquinian false religion, voicing his opposition to it as did the Reformers guided by the Byzantine/Majority Greek texts that had been restored to prominence by Desiderius Erasmus (the true father of the Reformation), and no longer distracted by the uninspired erring Latin Vulgate interpretation or its child--the RCC Catechistic dogmatic published formulae. Eh?
What you need to realize that since the time of Aquinas, uninspired use of natural reason and its logic--though profoundly increasing the magnitude of human knowledge--has nonetheless led mankind away from God and into atheism and greater depravity, recognizing neither an eternal spiritual realm nor the soul-destroying dangers of ignoring it.
And that's where your line of thinking leads the unwary and foolish person who professes Christianity but does not possess it and is not permeated by its change of character nor the processing of one's experiences according to Gods unchangeable point of view rather than by the fickleness of human reasoning.
God says, "Come let us reason together, though your sins are like scarlet they shall be white as snow".
Seems to me like God gave us a mind and still expects us to use it to reason. But the key phrase is "reason together"
If we had lost the ability to reason then how could we be held accountable for our sins?
But Rom 1:20 says " For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that people are without excuse."
I don't believe God expects total blind faith from the start. He gives us a base of information to reason from. What we do with that is up to us.
That base includes creation, prophecies, miracles, scripture, and works. "John 14:11 Believe Me that I am in the Father and the Father is in Me; otherwise believe because of the works themselves."
We are also told "That the heart of man is deceitful" and to "Trust in the LORD with all your heart and lean not on your own understanding;" and "Prov 4:23 Above all else, guard your heart, for everything you do flows from it."
The heart influences our reasoning. So much so that Jesus referred to "reasoning in your hearts", Luke 5:22-26 “Why are you reasoning in your hearts? Which is easier, to say, ‘Your sins have been forgiven you,’ or to say, ‘Get up and walk’? But, so that you may know that the Son of Man has authority on earth to forgive sins,”
Here you have an example of God not only providing evidence to reason with but also correcting our reasoning.
We must still use reason to come to the point of believing that God exists and trusting God. And that's the point where faith takes over in my opinion. We trust in the goodness of God and we study his word to learn more of his nature and truth that may not be obvious to our own reasoning. And our faith grows.
And a man's heart is key in whether he will choose to seek out God or hide in darkness. "John 3:19 This is the verdict: Light has come into the world, but people loved darkness instead of light because their deeds were evil. 20 Everyone who does evil hates the light, and will not come into the light for fear that their deeds will be exposed. 21 But whoever lives by the truth comes into the light, so that it may be seen plainly that what they have done has been done in the sight of God
Knowledge of God is imprinted on the heart and abundant in the creation around us. Knowledge of God's plan of salvation does take hearing. But the condition of the heart determines whether a person will choose to listen.
Romans 10:4 How, then, can they call on the one they have not believed in? And how can they believe in the one of whom they have not heard? And how can they hear without someone preaching to them? 15 And how can anyone preach unless they are sent? As it is written: “How beautiful are the feet of those who bring good news!”