no doubt, Herr Ratzinger certainly says a lot of sensible and intelligent things in this book and I'm not so blind as not to see that there is a certain need and Daseinsberechtigung for this brand of apologetics that tries to 'speaks the language of the culture' (altho I'd argue Ratzinger's ductus is oftentimes more reminiscent of a Heideggerian "Jargon der Eigentlichkeit") and 'engage the modern world' - but in enganging the world one should always be mindful to be "in it, not off it" and after reading this book you really do have to wonder "La nouvelle théologie, où va-t-elle ?", might it lead certain agnostics to a deeper understanding of the faith? quite possibly. Is this 'faith' the one apostolic, catholic faith? one has to wonder.
Certainly, with goodwill most everything in this book could be interpreted as orthodox; but that is the problem, it quickly becomes a Rorschach test, and the more discerning reader might a find a lot to take offense at; in many ways we find here the same 'weaponized ambiguity' that we have come to know and love from the conciliar documents and it certainly breathes the same anti-traditional air.
This manifests firstly in the view of Scripture. Through endorsement of the so-called historical-critical method Ratzinger essentially denies the character of Scripture as 'divinely inspired'. Instead of the holy Prophets we get neat distinction between 'authors of the book of Isaiaha', instead of Israel being chosen by God, we read that 'Israel chose a God that was such and such', as if one day Abraham and Moses had coffee together, musing about how their God should look like. Well, one might object, if this is what contemporary science tells us why not run with it? However this is only a sympton of a much deeper problem. If scripture is just the result of a historical process, if the story from Abraham to Christ is just the story of an increasing differentiation in the understanding of God, a Hegelian 'coming-to-itself' of Geist instead of a true supernatural revelation, then also Tradition turns into a mere 'factum' of a process, instead of the result of the providential workings of the Holy Spirit in history. And, as Ratzinger himself points out in his cirticism of Marxism, a historical 'factum' always begets a 'faciendem', which we see in his approval of the disgraceful ideas of Teilhard de Chardin.
You thus get a primacy of modern science over tradition, which ofc implies an hegelian view of progress and the Teilhardian conclusion that modern science can tell us more about God than the Doctors and Saints of the Church. As Burkhard, in his critique of Teilhardism, puts it pointedly: "The poor saints! They came a million years too soon. None of them, however, would ever have accepted the doctrine that God could be reached biologically, or again through collective scientific research."
But ofc, not only are the Saints and Doctors surpassed in their (meta)physical knowledge by modern science, but also, this follows logically, by the Nouvelle Théologie, which is just so much more 'enlightened' than those primtive medieval minds; an attitude reflected in the condenscending manner with which the New Theologian speaks of the "manual-theology" (i.e. the perennial philosophical tradition of the Church), an inherent hybris best expressed in the anecdote of Alfrink plugging the microphone of the old and half-blind Ottaviani during the council. In fact when actual Catholic Saints are quoted, which is rarely (mostly Augustine and Anselm; not counting ofc the evangelists) it is often so as to 'correct' their 'old-fashioned' views: "Those were the silly medievals, now ofc we are enlightended and so on" - what a farce! what ignorance, considering that the medievals possesed a religious genius far surpassing the shallow modernism of Ratzinger et al. The New Theologian, enlightened as he is, sees Scripture as an historical document of a certain Zeitgeist and culture; he is able to neatly distinguish the four authors of the pentateuch and can show you exactly where the "jah" in Moses' revelation of the divine name etymologically developed. How much deeper are the medieval scholar's '4 Senses' and the science of typology developed in Alexandria and refined by Augustine.
This difference might be illustrated with a trivial, yet emblematic example: In a lot of medieval sermons we mind find a reference to the Eva-Ave reversal when talking about the announciation. The New Theologian would ofc only sniff disparagingly at such sill word-games and he surely would be quick to point out that the Hebrew word is obviously different, how the latin might even be an imprecise translation from the original greek, he might even show when this word-play developed and in which historical conditions and so on and so on. But ofc the medieval preacher knew perfectly well that the angel wouldn't have said "Ave" in 1st Century Palestine; he nevertheless saw working through this reversal the mystical hand of providence; for him Latin isn't just as a random language, it is the language prefigured in the inscription above the Cross (INRI), destined from the time of the creation of Eve, to be the language of the New Eve (the Roman Church), so that at the time she bit the apple the reversal ('Ave') was already mystically present.
In summa: Tradition is not a 'factum', not even, as Ratzinger seems to imply, a 'collective factum', it is revelation, the 'primacy of acceptance' (to quote Ratzinger again), of what is received; the primacy of the objective over the subjective (these princples might, for example, be illustrated through the sacred art of eastern Icon-Writing, and their tradition of Acheiropoieta images).
Despite all of the above, this is not a bad book by any means, but it is not a catholic book, it is a book befitting the average protestant academic, not a Pope. It is the most insidious kind of religious 'conversativism' (the same brand that in politics fails to conserve anything). -- Yes, yes, indeed, the conciliar conservatives are the good guys after all; they seek for a real hegelian mediation between the Scylla of the 'evil traditionalists' and their 'manual-theology' and the Charybdis of the crazy liberals with their accoustic guitars; they want to be 'orthodox', but 'enlightened', they want novelty, but with a 'hermeneutic of continuity', not a revolution, by any means, but a 'Reformation', seems to them like a reasonable via media. Symptomatic of this attempt at a via media is also the constant 'push and pull', by which Ratzinger quotes arch-heretics like Bultmann and then immediatley retracts by saying "well, well, this is ofc hyperbolic and problematic", or "there are ofc a lot of trouble with the formulation" -- "but ... we see here an important aspect"; "Yes, yes, certainly; turning the Church into just a 'social club', now that would go ofc too far -- but, saying it is the New Ark out of which there is no salvation, would is ofc outdated ecclesiology" and so on and so on.
I do not deny that there are many enganging thoughts to be found here but, as we know, even the Devil quotes scripture and mixes Truth with falsehood; in the end there is no synthesis of True and false, no hegelian 'higher third' between Christ and Antichrist. This conciliar conservatism turn out to be just the same old modernism in new wineskins, which is and will always be the "synthesis of all heresies", as Pius X said.