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A Brief Review of Livi’s Book “Reasons for Believing”

REASONS FOR BELIEVING, BY PROF. ANTONIO LIVI The Davies Group Publishers, Aurora, Col. 2005   A review by  Raffaella Petrini     Before the challenges posed to us by modern skepticism, the words of our Holy Father, Benedict XVI, in his recent speech at the University of Regensburg, in Germany, sounds...

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(updated February, 2016)


On the relationship between Christian doctrine and philosophy

“Is Aquinas’ «Rationalism» Really Different from Bonaventure’s Thought?”, in Sensus Communis, 5 (2004), pp. 69-100.

About common sense knowledge, alethic logic, and foundation of metaphysics

“Has Common Sense a Real Relevance in Philosophy?”, in Sensus communis, 2 (2001), pp. 489-491.

“Does «Common Sense Philosophy» finally Eliminate Common Sense? A New Dialogue”, in Sensus Communis, 4 (2003), pp. 243-261.

“The Philosophical Category of «Faith» at the Origins of Modern Skepticism”, in Nova et vetera, English edition, 1-2 (2003), pp. 321-340.

“Modern Philosophy and the Origins of Catholic Fideism”, in Aquinas, 46 (2003), pp. 234-245.

“A Reply to Santiago Zabala”, in Sensus Communis, 5 (2004), pp. 440-448.

“Religious Experience, Grounded Upon the Evidence of Common Sense”, in Sensus Communis, 5 (2004), pp. 359-373.

A Philosophy of Common Sense. The Modern Discovery of the Epistemic Foundations of Science and Belief, The Davies Group Publishers, Aurora (Colorado) 2013.

«Why the relative Truth of any Scientific Statement Presupposes the Absolute Truth of Common Sense”, in Antonio Livi (ed.), L’istanza critica, tra senso comune e scienza, Casa Editrice Leonardo da Vinci, Roma 2013, pp. 33-40.

«Why Common Sense,  When Assumed as The Primary Truth, Furnishes Alethic Logic System With its Very Epistemic Justification »,  in La certezza della verità, a cura di Antonio Livi, Casa Editrice Leonardo da Vinci, Roma 2014, pp. 19-30.

The Holistic Theory of Truth and the Epistemic Primacy of Common Sense Among  All Kinds of Ordinary Knowledge, in Epistemology of Ordinary Knowledge, edited by Mariano Bianca, Cambridge Scholars Publishing, Newcastle upon Tyne (UK) , 2015, pp. 117-126.

The Issue of Alethic Logic, in Science between Truth and Ethical Responsibility. Evandro Agazzi in the Contemporary Scientific and Philosophical Debate, edited by Mario Alai, Marco Buzzoni, Gino Tarozzi. Springer International Publishing, Cham (Switzerland), 2015, pp. 163-178.

On the rationality of believing  in Christian revelation

“Modern Philosophy and the Origins of Catholic Fideism”, in Aquinas, 46 (2003), pp. 234-245.

Reasons for Believing. On the Rationality of Christian Faith (“Contemporary European Cultural Studies”,  n. 1), The Davies Group, Aurora, Colorado 2005, pp. 168.


Understanding Christian faith and living it

Marian Coredemption in the Ecclesiology of Cardinal Charles Journet, in Alessandro Apolloni (ed.), Mary at the Foot of the Cross, VII: Corredemptrix, therefore Mediatrix of All Graces, Academy of the Immaculate, New Bedford, Massachusetts 2008, pp. 355-366.


William Slattery, The Logic of Truth. Thomas Aquinas’ Epistemology and Antonio Livi’s Alethic Logic, Rome: Casa Editrice Leonardo da Vinci, 2015.


by Antonio Livi

Some Italian scholars (Pier Paolo Ottonello, Roberto Di Ceglie, Fabrizio Renzi) have already tried to draw a synthetic overview of my logical thought. William Slattery is the first non-Italian scholar who did it, and I sincerely think that his attempt is the best one, both for its completeness and for its intellectual penetration in the matter. So it is now for me a pleasure to present it and to recommend it to all who are concerned with the contemporary discussion about the issue of truth.

William Slattery, an Irish priest living in Rome, was studying Philosophy at the Gregorian University, where he defended in 2015 his doctoral thesis, whose subject was my own interpretation of the main principles of Thomas Aquinas’ epistemology. The book that now I have the pleasure to present is just based in the conclusions of  the research performed for his Ph.D. This research deals with my proposal of systematizing and updating the philosophical thought of Saint Thomas in relation with the key problems of epistemology, trying to connect in a logical system his main doctrines, i.e: i) the metaphysical nature of logical truth, as adaequtio intellectus ad rem; ii) the primacy of direct experience over both reasoning and faith in a witness; iii) the alethic function of the first principles of knowing as the common background of all possible achievement in the search for truth; iv) the judgment as the reflexive act of the mind by which the thinking subject express his consciousness of having reached the truth about some concrete object in a certain moment. In order to perform this project of systematizing and updating the philosophical thought of Saint Thomas in relations with those topics, I took advantage of the modern notion of “common sense” which had been developed by several philosophers, not necessary belonging to the Thomistic tradition, in their defense of metaphysical realism, before against Descartes’ idealistic system and after against Kant’s transcendental system. Moreover, I took advantage of the contemporary logical achievement of the American scholars belonging to the analytic school. For this reasons, Slattery’s attempt to perform a critical comparison between the doctrines of Saint Thomas and my alethic logic system was really very difficult, especially because it required a deep penetration in the very meaning of the different terms used by Aquinas and modern and contemporary philosophers.

But Slattery was capable to overcome those difficulties. He reached an excellent degree of comprehension of Aquinas’ thought  having spent many years to an attentive reading of all his epistemological works. And, for what concerns my own thought, he spent almost three years to read my books on the alethic logic and to meet me personally in order to discuss about the right interpretation of what I wanted to maintain. He was really able to show that what I defend with my ‘philosophy of common sense’ is precisely the epistemic primacy of common sense among all kinds of ordinary knowledge in order to save a holistic theory of truth. But he was also capable to underline my own notion of “common sense” –which is very different from the sociological or the psychological one, since it pertains to epistemology, which is the main issue of philosophical logic. Actually, my philosophy of common sense should be understood as something similar to what Roderick Chilshom called ‘the foundations of knowing’. In other words, common sense, as I conceive it, is the first step of a theoretical process which leads to overpass the simply semantic holism, i.e. the holism of meaning, in order to take in account the alethic holism, i.e. the holism of truth. This is made possible by detecting a set of logical connections between judgments based on the truth as the basic value of judgments. The result is an axiomatic system of epistemic logic based on the acknowledgement of the real dependence of every judgment on the truth of its necessary presuppositions, or logical conditions of possibility for it to be true. This is the meaning of what I maintain as the basic law of thinking, according to the most rigorous phenomenology of the mind processes – which are all directed, in any case, to the consciousness of truth, i.e. to the certainty that the contents of my judgment, here and now, is really true, and I cannot absolutely suppose the contrary to be true. This can happen only when my judgment is strongly founded in its presuppositions, so that I realize that it is just the necessary result of all true knowledge I have already obtained and assured with my former certain judgments. Then, this is the general framework of what I conceive as the holism of truth. According to this logical system, any thought of truth –and any assertion which can express it– is linked with all the others thoughts in its very epistemic justification, through the need of finding its own premise and presuppositions.

In such a holistic system of alethic logic, my notion of common sense retain a very narrow extension, since it refers only to few, well determinate primary certainties which are the common presupposition of both ordinary and scientific knowledge in all their forms and in all their degrees. In others words, “common sense” is in my logical system the very hard core of the holistic structure of truth. I reached such a conclusion taking in account the basic date of the cognitive science, the most advanced studies on the philosophy of mind, and the best results of the phenomenology of consciousness – which makes use both of subjective introspection and the analysis of the inter-subjective communication. I realized that in the consciousness of every thinking subject there are some certainties about the ‘real world’ –certainties whose epistemic justification is founded on the immediate evidence of existing beings which necessarily and always are present in everyone’s experience-

But I maintain much more. In my system such certainties constitute the very first link in the chain of presuppositions; so that they can in no way be subject to doubt. This means that their non-truth is absolutely unthinkable: actually, no one can ever really doubt them, and one must understand that any affirmations to the contrary are merely verbal posturing: actually, they respond to some pragmatic logic, and not the expressions of a real certainty, endowed with its own adequate epistemic justification. Given that they constitute the nucleus of experience, understood as a body of unmediated knowledge, such certainties are present to consciousness in every moment of the search for truth as the logical presupposition of all knowledge deriving from reflection and inference, both inductive and deductive. For this same reason, such certainties function as an ultimate criterion of truth to verify any hypothesis successively formulated. They therefore constitute the main alethic presupposition, that is, the presupposition necessary for any ulterior knowledge to be thought of as true. In fact, on the basis of these original truths, every thinking subject verifies, time after time, the admissibility of any hypothesis – formulated by himself or proposed by other subjects through one of the ways for communicating thought – that presents itself in the search for other truths over the course of his lifetime. As a result all scientific knowledge, should be structured as system logically compatible with the primary truth of common sense, so as to place the instruments of dialectics (reflection, interpretation, inference) effectively at the service of the search for further truths.

Author’s Foreword

Numerous critical appraisals published after the first Italian version of this essay[1] have confirmed my strong conviction that the subject of the rationality of Christian faith is truly crucial in today’s cultural world, both in terms of philosophy and of theology. I have been able to clearly see that fideism (as I have been pointing out for some years now[2]) has been and continues to be the major danger regarding the faith. I have also seen that the attempts on behalf of the Magisterium to warn the faithful of this danger have not been heard nor followed, perhaps because they have not been received nor transmitted to catholic public opinion by those who would have both the means and duty to do so; obviously, I am referring to John Paul II’s Encyclical, Fides et ratio, but also to many magisterial interventions that have preceded and followed this historical document.

I also need to recognize in this Preface to the American version several helpful critiques that have been offered by friends and colleagues. One of these, in a long and accurate commentary[3], noted that his theologian of choice, Karl Rahner, was scarcely quoted in my essay: To this I can not answer that I have since added more references of that German scholar, because I have not, given that I hold that Rahner’s thought is not compatible with the philosophical questions that are most important for me, which are those concerning ‘the truth of thought’ in relation to Christian faith; Rahner has many and unanimously recognized theological merits, yet his philosophical point of departure suffers from Kantian transcendentalism in that form of ‘Transcendental Thomism’ which made his mentor Joseph Maréchal famous, and who was criticized at the time by the French philosopher Etienne Gilson and the Italian philosopher Cornelio Fabro, both of whom I regard as my mentors, sharing both their principles and methods. Another friend of mine, who has got as his mentors the Italian philosopher Gianni Vattimo together  with the American Richard Rorty, wrote that [4]

In other commentaries I have noticed certain perplexities about the vision which informs my investigations on the faith of Revelation. If they were from theologians, involved in what is called ‘Fundamental Theology’ which deals with supernatural revelation and faith, I well understand the difficulties they encounter in accepting a conversation which necessarily deals with themes which are also theological in nature, but which attempts to discuss them in a philosophical environment. The distinction between fundamental theology and a philosophical discipline such as alethic logic is the following: in fundamental theology we are dealing with theological investigations, which, to the degree in which they remain faithful to their specific method and epistemological status, begin with the fact of faith accepted as such (as the thought of a believing subject) and then proceed and arrive at conclusions while staying within the environment of faith itself; in alethic logic, on the other hand, we are dealing with an attempt at scientific knowledge which begins with common human experience and natural reflection (in and of itself foreign or prior to the act of faith, and always epistemologically independent of that act) in order to reach some ulterior understanding of empirical data, while remaining within these strict boundaries. As a result, if philosophy (from the point of view of alethic logic) becomes concerned with faith in Revelation, such analysis should be understood as dealing not with the act of faith (fides qua creditor) as a personal and ineffable experience of the believing subject (this act can not become an object of investigation ‘from the outside’ of the personal consciousness of each person, much less an object of universal scientific analysis), but rather with the universal characteristics of the act of faith ‘viewed from the outside’, as certain knowledge of something, obtained through the acceptance of qualified testimony (in this sense, the philosophical analysis of faith in Revelation will become part of a wider conversation, i.e., a properly epistemic conversation concerning the conditions of possibility of knowledge through faith in general). If we later deal with the content of the act of faith, i.e., ‘the doctrine of faith’ as object of that act (fides quae creditor), we must affirm that the sacred texts, Tradition, Magisterial documents and dogmas are not taken into consideration as ‘sources’ of the scientific truth that is sought, and even less as ‘arguments’ demonstrating some philosophical thesis: they are instead taken into consideration in their ‘formal aspect’, i.e., in order to examine that which ‘they desire to assert’, that which they propose for belief, in other words, their rational content; that content which can be the object of the philosopher’s logical investigation, just as – independently of philosophy – it can be the object of even a minimal degree of a believer’s understanding, within the dynamics of the act of faith. Here we must admit – and I gladly admit this because it is true, and also because it does not take away anything from the aforementioned investigation – that such an investigation proceeds ‘from the outside’, in quite a different way from any theological investigation, including that of fundamental theology[5]. There have also been equally ambiguous and somewhat irrelevant observations made by those who examined my book through the prism of a different philosophical discipline than the one proper to it, i.e., the philosophy of religion; in fact, the philosophy of religion is limited to delving into religious phenomena in general, and may have as one of its goals that of showing the connection between the religious phenomenon as a social and historical fact and religious consciousness as a necessary and universal dimension of fundamental human experience, i.e., as one of the components of ‘common sense’. I share this point of view, and in other writings, I have asserted the duty of philosophy to pursue such a goal[6]; yet the philosophical analysis of the faith in Christian revelation is another story, because it is nor longer a question of studying religion as such and universally, much less of studying the so called ‘positive religions’ as historical forms of the one and only ‘natural religion’, each one with its own claim to truth, perhaps even on the basis of a presumed divine revelation; it is a question, rather, of directly studying the Christian religion from the point of view of its specific doctrinal content, as a result of which the subject that believes in it, i.e., holds it to be true, in the sense that he makes it his own not only as true but as the only absolutely true religion – assumes particular criteria of verification.

Having made these necessary distinctions, we must now recognize that the philosophical analysis of the faith in Revelation, carried out through the prism of alethic logic, is aware of the most valid results of the philosophy of religion, and has much to say concerning the theological conversation carried out by Fundamental Theology scholars (who are actually the most common quoted authors in my book). The reason for this is that when faith reflects on itself, that which emerges from this reflection is precisely the rational dimension – of ‘natural reason’ – which characterizes the faith in revelation, both as an intellectual act of the human subject who requires ‘reasons’ for believing (preambula fidei), as well as intrinsic contents of the revealed doctrine, which certainly consists of supernatural mysteries which transcend all human understanding; yet, inasmuch as it is the Word of God offered to man, it is endowed with that (relative) intelligibility and that (absolute) plausibility which allow human reason to detect in the Word the ‘necessary arguments of credibility’ (motiva credibilitatis). Those Fundamental Theology scholars who have appreciated my work have realized that I have further explored many lines of reflection offered in the Encyclical Fides et ratio, which, as I have many times underlined, is precisely a reflection that ‘fides’ directs towards itself, discovering in herself an intrinsic unity with ‘ratio’.

One last observation concerning the image on the cover: I did not want to change it, simply because there is no other picture more relevant to the theme I am treating. Primarily, the episode of the dialogue between Thomas the Apostle and Jesus is dealt with in the central part of my essay; yet the entire logic of my essay derives from the situation that Caravaggio has rendered immortal – the Word of God made man who reveals to us his divinity and his Father’s plan of salvation; the Apostle who did not want to believe the testimony of the other apostles who had seen the risen Christ; the most explicit proclamation of Christian faith, formulated by Thomas himself with the words (to be understood as an affirmation and not invocation): «My Lord and my God!». In the heart of this episode we find the Body of Christ: Jesus has truly risen with his very body, and he has wanted to conserve the wounds of his passion so that they remain for all eternity the sign of the truth of Redemption; and Thomas rightly demands – given his calling as a ‘witness to the resurrection’ – empirical evidence of the glorified body of the Lord, evidence which – united to reasoning – is transformed in his conscience into the certainty of faith that Jesus is God, as he revealed to those who were his own in the world and as he had declared in front of the Sanhedrin. The words of Jesus that close the episode indicate the difference between the faith of the Apostles and the faith of us who have heard about the Gospel after Jesus was no longer visible among men: the faith of the Apostles is based on the empirical evidence of the fact of the bodily Resurrection of Jesus, correctly interpreted as ‘the sign of Jonah’ and therefore as an argument of credibility in order to ‘take the words of the Master as true’, in an absolute sense. Our faith, on the other hand, must be based initially on the testimony of the apostles, without which we can not know with certainty that Jesus lived, died and rose according to the Gospel narrations (and without knowing this we would not have arguments of credibility in order to ‘take the words of eternal life as true’ which the Lord has proclaimed for our salvation).

Antonio Livi

Rome, October 2003

[1] Cf. Antonio Livi, Razionalità della fede. Un’analisi filosofica alla luce della logica aletica, Rome: Leonardo da Vinci, 2002.

[2] Cf. Antonio Livi, «Il pericolo è il fideismo», in Studi cattolici, n. 24, 779-784.

[3] Cf. Angelo Marchesi, «Un’impegnata analisi del rapporto tra ragione e fede nel pensiero contemporaneo», in L’Osservatore Romano, September 21, 2003, 7.

[4] Cf. Santiago Zabala, «Ending the Rationality of Faith through Interpretation», in Aquinas, 47(2005), 89-110.

[5] In a recent Convention held at the Lateran University of Rome, several scholars of fundamental theology (among which we find Rino Fisichella, Salvador Pie i Ninot and Hermann Pottmeyer) criticized some tendencies within their discipline to transform fundamental theology into a merely philosophical treatise of an ‘preamble’ nature. Whatever may be the soundness of the criticism that certain theologians level against this tendency, such criticisms do not apply to the validity of the method that I use in this study, given that I do not intend to offer new hypotheses regarding fundamental theology but rather to apply the exclusively philosophical categories of alethic logic to the human experience of faith in Revelation.

[6] Cf. Antonio Livi, La ricerca della verità: dal senso comune alla dialettica, 2nd edition, Casa editrice Leonardo da Vinci, Rome, 2003, 166-180.


Santiago Zabala
Santiago Zabala
Santiago Zabala is ICREA Research Professor of Philosophy at the University of Barcelona. His books include The Hermeneutic Nature of Analytic Philosophy (2008), The Remains of Being (2009), and, most recently, Hermeneutic Communism (2011, coauthored with G. Vattimo), all published by Columbia University Press.

He spoke about Antonio Livi’s thought in two main occasions:

i) with a contribution to the book Per una filosofia del senco comune, Edited by Philip Larrey (Milano: Italianova, 2009);

ii) with an essay published in  the journal Sensus communis – International Yearbook for Alethic Logic (2010).