Can One Detect in Agazzi an Implicit Theory of Alethic Logic as Unifying the Presuppositions of All Kind of Knowledge?

The emphasis that Agazzi puts on the truth-value (which is the central value of knowledge if it is considered from a logical point of view) made me understand that Agazzi’s arguments fitted perfectly with what I maintained from the begin­ning, i.e.

Antonio Livi, a contemporary thinker who has devoted a deep reflection to the theme of common sense philosophy, starts from the point of view according to which philoso­phy aims at attaining truth in a full and absolute sense, by using rigorous logical meth­ods that do not reduce to the pure requirement of formal correctness, but aim at attaining the possession of truth (alethic logic). In this task philosophy cannot avoid scrutinizing the purport of pre-philosophical knowledge that presents itself as true, and that consti­tute its starting point (i.e.

In the same essay Agazzi declared himself to be in perfect agreement with me even when the topic was the relationship between common sense and scientific thought (both physical and metaphysical). So he says:

Antonio Livi underscores the reasons for which metaphysics, understood as a rigorous and truth-bringing philosophical discipline, cannot avoid referring to common sense.

2.1 What Precisely ‘Common Sense' Means in the Alethic

System Proposed by Agazzi

The difference between Agazzi’s way of conceiving alethic logic and mine can be detected when Agazzi expounds what precisely he means by the term ‘common sense’. Actually, the evaluation of how much scientific knowledge is founded on pre-scientific knowledge depends directly on the definition of the epistemic func­tion of common sense. If common sense is meant as the logical system of the first undeniable truths based on direct experience, then the truth-value of any scientific research depends on the truth-value of common sense (this is just what I maintain). On the contrary, if common sense is meant as a vague complex of popular opinions or pre-scientific interpretations on the facts of experience (this is just what Agazzi maintains), then the results of scientific research have to be evaluated as more cer­tain and more founded with respect to common sense views of the world.

The first step of Agazzi’s research on this issue was a critique of the traditional opinion held by modern scientists and philosophers of science. Actually, they main­tain that all scientific knowledge, while being sometimes merely hypothetic, is opposed to common sense, either through a direct falsification or through an indi­rect demonstration that it is impossible to think it is true. Agazzi, after clarifying the primary criterion of truth as that of ‘evidence’ (referred both to sensible data and to rational principles), denies the identification of ‘evidence’ with ‘immediate experi­ence’: the former is, according to his language, something purely rational, while the latter is a popular belief, something obvious. On the basis of this distinction, he de­constructs my theory of common sense certainties as the primary truths, since com­mon sense seems to have a constitutive lack of rational self-justification:

The contents of common sense have the characteristic of shared opinions that are such in a spontaneous and non-reflexive way. Therefore, they are accepted as obvious. The con­victions of common sense, however, are characterized by the fact of not “exhibiting” the credentials of their soundness, since they are spontaneous and non-reflexive and the only indirect support for their soundness seems to be represented by the fact that they are very widely “shared”, and this more or less amounts to saying, “How is it possible that we all are wrong?” and this is obviously not a very strong argument. It can be reinforced, how­ever, when one underscores that such a very wide acceptance of such beliefs depends on the fact that they do not need a special effort in order to be clarified and founded, that they impose themselves spontaneously, that is, that they are obvious.

Agazzi offers some examples which show that the scientific explanation of phenomena does notdeny the common sense sensible evidence:

Let us consider again a common sense “sensible evidence”: the fact the sun appears at a certain point of the horizon at morning, it covers an arch in the ski during the day and disappears under the horizons at a different point at sunset. A way for expressing this complex evidence in a compound judgment is the following: the sun moves in a circular motion around the resting earth during a revolution period of 24 h. This offers the “why” or the “rational explanation” of the mentioned sensible evidence. In this judgment, how­ever, are unconsciously used the concepts of motion and rest as “absolute” properties of the bodies and, in particular, the property of being in a state of absolute rest is attributed to the earth (“geostatic” conception). Nevertheless the same sensible evidence can be ration­ally explained by saying that the sun finds itself in a state of absolute rest and the earth rotates on itself with a rotation period of 24 h (“heliostatic” conception). The two concep­tions turn out to be even equivalent if rest and motion are conceived as properties “rela­tive” to a given system of reference and their ascertainment is related with the fact that the observer be linked with the one or the other reference system. Assuming that the earth constitutes the “natural” reference system is again a common sense conviction that, nev­ertheless had to be abandoned for cogent reasons when “heliocentrism” has superseded “geocentrism”.

I think that Agazzi’s argument is in itself perfectly correct. It contributes, together with many other arguments, to the development of Agazzi’s continuous and severe critique of what he calls ‘scientism’ (see Velazquez 2012). But it does not deal with what I mean when I speak about ‘common sense’. I don’t refer to the popu­lar beliefs existing in each time about the cosmological order. All beliefs of this kind are always changing according to the different ages and cultural environ­ment in which they are born. On the contrary, the beliefs I refer to belong to every man in every time and in every cultural environment. In relation with such kind of beliefs physical science cannot ignore them, because scientists are themselves thinking subject starting from those evident data in their own scientific research. Actually, no scientist can really think that they are not true. A scientist can only correct some popular interpretation of those data if they seem inadequate. The sci­entific aim is not to deny the truth of common sense beliefs, but to furnish human knowledge with a correct causal explanation of what everybody already knows, i.e. to discover, when it is possible, the cause (material, formal, efficient and final) of each event belonging to the physical world. I can quote, in this regard, what an American scholar correctly said:

Some might object by pointing out that many conclusions of contemporary science seemingly contradict common sense knowledge, e.g., quantum mechanics, or strange astrophysical phenomena. The response is that technical scientific conclusions offer expla­nations of certain phenomena beyond the proper context of common sense (either in a very small context or a very large one), yet they do not deny the irreplaceable value of common sense for its own context. To assert that Copernican astronomy or Einsteinian relativity contradict our common sense knowledge of the world implies a misunderstand­ing of what common sense knowledge is. In the pre-Copernican understanding of the world, the assertion that “the Sun revolves around the Earth” would not have been con­sidered a principle of common sense as fundamental as, say, “the external world exists”, but rather as a quite natural and spontaneous explanation of the phenomena we all observe everyday. That “natural explanation” has been replaced with a truer one, even though the observed phenomena did not change in any way and the core principles of common sense were not contradicted. We still refer today to the Sun as moving from East to West in the sky, even though we know that in fact is the Earth which moves; this does not contra­dict common sense, as the notion that “there are no objects” or “the sun does not exists” would. This is precisely the way in which proper scientific discovery comes about, in con­tinuity (and not in contrast to) common sense knowledge (Larrey 2007: 46).

2.2 Has Common Sense an Alethic Primacy in the Epistemic System Proposed by Agazzi?

I think that a dialogue between particular sciences and metaphysics is certainly necessary, and de facto always beginning anew. However, the threats of recipro­cal interference or methodological commingling can be avoided, as can attempts to annex one to the other, deriving from epistemological errors (as in the age of classical philosophical cosmology or the age of modern positivism) if a basis of conceptual agreement is found. This basis can be found precisely by returning to the common epistemological derivation of the certainties and contents of direct experience, thus circumventing any attempt at an impossible, unmediated transla­tion (without the mediation of those basic certainties) of the technical language of metaphysics into the technical language of the other sciences, or vice versa. I main­tain that the organic body of certainties of which I speak is in itself qualitatively superior to science, including within the notion of “science” both the metaphysi­cal as well as the particular sciences, that is, all reflexive and systematic knowl­edge, mediated by reasoning and by culture and equipped with its own technical methodology. The superiority of those certainties lays precisely in the quality of the certainty itself. While the certainty of those direct and universal statements is unconditional and absolute, scientific certainty always has limiting characteristics: either it is a subjective certainty linked to privileged conditions of experience or intellectual capacity; or it is a certainty available only to members of a specific cul­tural community equipped with its own research instruments; or it is a certainty that can be reached by all humankind, only in relation to particular historical events, or a certain historical level of technological development, or a particular histori­cal perspective on human events; or it is a provisional (hypothetical) certainty, sus­ceptible of falsification or at least revision and adjustment, when it is not a bold working hypothesis of an instrumental nature (that is, as an efficacious tool for research, for science itself, or a mere instrument at the service of technical work or other practical ends). So, while common sense certainties are incontrovertible, any science certainty is debatable, or at least relative, perfectible, revisable; the former belong to all people at all times, the latter belong to some people and only in spe­cific moments of personal or collective history. Secondly, the superiority of these certainties over science is also a primacy in truth: they come first, both logically and chronologically (because every reflection presupposes some direct knowledge to which to return), and are also elevated above other certainties, in the sense that they cannot be contradicted (that is, proven false), to the point that every scientific thesis that contradicts those certainties is for that very reason vitiated by error (even if that error can only be demonstrated at the level of science).

2.3 The Meaning of ‘Common Sense' in Agazzi Pertains More to the Sociological Tradition then to the Epistemic One

Summing up, it can be said that in my holistic system of truth I use the term ‘com­mon sense’ in its properly alethic meaning, while Agazzi accepts the usual socio­logical or psychological meaning. As many contemporary essays on this topic, he stands in the tradition of past and current common sense philosophers, like Thomas Reid, George Berkeley, Henry Sidgwick, George E. Moore, James B. Conant, Radu J. Bogdan, and NohaLemos, who defend common sense against rationalism in phi­losophy and in science. Some other thinkers go beyond their accounts by not only defending common sense but also considering what common sense means (cf. Davidson 1984; Boulter 2007; Piccari 2011). Unfortunately, no one of these schol­ars realized the possibility and the necessity of passing over the limits of the phe­nomenological research (social psychology, cultural anthropology, sociology of culture, and so on). A clear example of this could be the research performed by the Swedish Marion Ledwig. Besides giving a historical exegesis of common sense in Thomas Reid and showing parallels in Austin, Searle, Moore, and Wittgenstein, he discovered common sense also in Hume’s An Enquiry Concerning the Principles of Morals and in Kant’s Critique of Pure Reason. But the final interpretation of com­mon sense made by this author does not reach at all the level of alethic logic. With his essay he aimed only to make clear how far common sense generalizes, whether proverbs are a form of common sense, and whether common sense can be found in the common knowledge assumption in game theory. Also, he holds that folk psy­chology should be considered as a common sense psychology (see Ledwig 2007). On the contrary, my own notion of common sense pertains to epistemology, which is the main issue of philosophical logic, as Evandro Agazzi himself acknowledges (see Agazzi 1981). Actually, my philosophy of common sense should be understood as something similar to what Roderick Chisholm called ‘the foundations of knowing’ (cf. Chisholm 1972), and John Searle calls “default position” (cf. Searle 1998: 10).

If understood in this epistemic meaning, common sense should be the first step of a theoretical process which leads to overpass the simply semantic holism, i.e. the holism of meaning (see Tarski 1944), in order to take into 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 (see Davidson 1990a, b). 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. 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 other thoughts in its very epistemic justification, through the need of finding its own premise and presuppositions. In such a holistic system, my notion of common sense retains 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 degrees. In others words, “common sense” is just the hard core of the holistic system of truth. I reached such a conclusion taking in account not only Agazzi’s philosophy of science but also the basic results of the cognitive science (see Smith 1995a), the ontologi­cal research performed by some analytic philosophers (see Kripke 1980), and the most advanced studies on the philosophy of mind (see Searle 2004), 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. In Searle’s philosophy of mind such permanent presence of some existing beings is named ‘original or intrinsic intentionality’:

Where the mind is concerned we also need a distinction between original or intrinsic intentionality on the one hand and derived intentionality on the other. For example I have in my head information about how to get to San Jose. I have a set of true beliefs about the way to San Jose. This information and these beliefs in me are examples of original or intrinsic intentionality. The map in front of me also contains information about how to get to San Jose, and it contains symbols and expressions that refer to or are about or repre­sent cities, highways, and the like. But the sense in which the map contains intentionality in the form of information, reference, aboutness, and representations is derived from the original intentionality of the map makers and users. Intrinsically the map is just a sheet of cellulose fibers with ink stains on it. Any intentionality it has is imposed on it by the origi­nal intentionality of humans. So there are two distinctions to keep in mind, first between observer-independent and observer-dependent phenomena, and second between original and derived intentionality. They are systematically related: derived intentionality is always observer-dependent (Searle 2004: 7).

2.4 How Agazzi’s Alethic Logic Is Limited by the Rationalist Roots of His Epistemology

In my system of alethic logic 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. They constitute the nucleus of ‘experience’, understood not only as a body of sensible data but as the body of any kind of unmediated knowledge. Much more, 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 further 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 a system logically compatible with the primary truth of common sense(see Nagel 1961), so as to place the instru­ments of dialectics (reflection, interpretation, inference) effectively at the service of the search for further truths(see Gadamer 1960).

Agazzi cannot agree with me on this issue because he holds that the logical form of common sense is only that of some popular believes which are largely shared but cannot be founded or proved, while their content is very difficult to be determined by the means of sociology of culture. For this reason Agazzi holds that it is impossible to avoid a hard opposition between common sense and science, or almost between common sense and reflexive, methodical and critical thought. So, all science of nature and much more metaphysics find themselves in basic con­flict with common sense. Evandro Agazzi, as many other scholars who were fol­lowers of Gustavo Bontadini (see Rivetti Barbo 1990; Carlani 1995), establishes a formal distinction between what is believed because it is obvious and what is believed because it is evident, while identifying evidence with incontrovertibil- ity. On the contrary, I think that many evidences—among which the primary evi­dences which constitute common sense—do not have the epistemic quality of an abstract rational incontrovertibility, since they show simply things existing and facts happening in the world, and this kind of reality is in itself something con­tingent, non-necessary. Nevertheless, the certainty we have about this is absolute, so that it is impossible that somebody can think that they are false, as I have said above. Something similar happens when Agazzi, adopts the distinction (introduced by Bontadini) between certainty and truth. For him, certainty is an epistemic prop­erty of a proposition: it expresses the way we are subjectively sure that what we have said is true, but this has no practical effect on its effective truth or falsity (cf. Agazzi 1997).