The Problem of Knowledge in the Western Tradition
Humanity in the course of the very complex and articulated history of knowledge, at least as it has unfolded in the context of the Western tradition, has generally fluctuated between two antithetic metaphysical polarities, like reversed and mutually exclusive mirror images.
In one of these polarities human beings have claimed to be able to actually know reality absolutely and definitively, as can be deduced already by the observations with which Galileo introduces his well-known distinction between sapere intensive (intensive knowledge) and sapere extensive (extensive knowledge), as explained at the conclusion of the first day of his less famous Dialogue Concerning the Two Chief World Systems of 1632 (Galileo 1968, VII, 128-131), where we read specifically the following:[...] the human understanding can be taken in two modes, the intensive or the extensive. Extensively, that is, with regard to the multitude of intelligibles, which are infinite, the human understanding is as nothing even if it understands a thousand propositions; for a thousand in relation to infinity is zero. But taking man's understanding intensively, in so far as this term denotes understanding some proposition perfectly, I say that the human intellect does understand some of them perfectly, and thus in these it has as much absolute certainty as Nature itself has. Of such are the mathematical sciences alone; that is, geometry and arithmetic, in which the Divine intellect indeed knows infinitely more propositions, since it knows all. But with regard to those few which the human intellect does understand, I believe that its knowledge equals the Divine in objective certainty, for here it succeeds in understanding necessity, beyond which there can be no greater sureness (english translation by Stilmann Drake).
[...] l'intendere si puo pigliare in due modi, cioe intensive o vero extensive: e che extensive, cioe quanto alla moltitudine degli intelligibili, che sono infiniti, l'intender umano e come nullo, quando bene egli intendesse mille proposizioni, perche mille rispetto all'infinita e come zero; ma pigliando l'intendere intensive, in quanto cotal termine importa intensiva- mente, cioe perfettamente, alcuna proposizione, dico che l'intelletto umano ne intende alcune cosi perfettamente, e ne ha cosi assoluta certezza, quanto se n'habbia l'istessa natura; e tali sono le scienze matematiche pure, cioe la geometria e l'aritmetica, delle quali l'intelletto divino ne sa bene infinite proposizioni di piu, perche le sa tutte, ma di quelle poche intese dall'intelletto umano credo che la cognizione agguagli la divina nella certezza obiettiva, poiche arriva a comprenderne la necessita, sopra la quale non par che possa essere sicurezza maggiore (Galilei, 1968: VII, 128-129).
This epistemological approach also explains why Galileo himself had then developed a substantially “cumulativistic” conception of the history of science itself, because he believed any knowledge could only be “absolute”, and could constitute an outcome on which new achievements and new knowledge, just as absolute and unchangeable, would be superimposed. Which also explains why, in the last phase of his life, after being condemned by the Catholic Church to life imprisonment, the Pisan scientist still held to the certainty that he had not wasted his life. If, in fact, his research programme certainly suffered a dramatic setback with the trial, his abjuration and his condemnation by the Catholic Inquisition, yet psychologically Galileo could still appeal to the satisfactory realisation that during his life he had nonetheless achieved “half a dozen true things”, and that these results would remain a definitive achievement for all humanity. For this reason Galileo could rightly conclude his argument:
I conclude from this that our understanding, as well in the manner as in the number of things understood, is infinitely surpassed by the Divine; but I do not thereby abase it so much as to consider it absolutely null. No, when I consider what marvelous things and how many of them men have understood, inquired into, and contrived, I recognize and understand only too clearly that the human mind is a work of God's, and one of the most excellent (english translation by Stilmann Drake).
Concludo per tanto, l'intender nostro, e quanto al modo e quanto alla moltitudine delle cose intese, esser d'infinito intervallo superato dal divino; ma non pero l'avvilisco tanto, ch'io lo reputi assolutamente nullo; anzi, quando io vo considerando quante e quanto maravigliose cose hanno intese investigare ed operate gli uomini, pur troppo chiaramente conosco ed intendo, esser la mente umana opera di Dio, e delle piu eccellenti (Galilei 1968, VII, 130).
This conception of the claimed absoluteness of human knowledge (which, from the theological point of view, is indeed true blasphemy, because it still puts man on the same level as divinity through science), had therefore already emerged with the genesis of modern science in the seventeenth century. But it has not disappeared since then, as it again coincides with the positivist dream itself (and also with the neo-positivist one), respectively of the nineteenth and twentieth centuries, on the basis of which the interplay of knowledge appears to these movements as a sort of puzzle, albeit extremely complex, in relation to which, however, humanity, in the course of time and the centuries, will finally succeed in gaining all the pieces.
Then, by putting them together, humanity will finally obtain an entirely conclusive and absolute picture of the knowledge of the world.In opposition to this tradition of metaphysical thought, decidedly optimistic about the overall result of human knowledge, there emerged a very different and conflicting metaphysical movement of thought which has constantly insisted rather on the intrinsic limits to our ability to know the world. Ever since the Greek origins of Western thought, the genesis of the tradition of scepticism has also constantly shattered precisely that metaphysical dream of absolute knowledge with undoubted acuteness and original criticism, showing all its many difficulties, contradictions, and undue assumptions, often completely unjustified (Dal Pra 1989). But in delineating, with undoubted acumen and absolute critical originality, this meritorious pars denstruens, scepticism has ended up most often by falling out of the frying pan of absolute metaphysical knowledge into the fire of a pragmatic, hermeneutic and equally absolute and metaphysical relativism which denies, apri- oristically and prejudicially, the very possibility of human knowledge about the world. Thus knowledge, as already stated by sophists in the fifth century BC and by supporters of hermeneutics in the twentieth century, is ready to reduce knowledge to mere opinion, to a senseless pun, reducing everything to an endless semiosis which would always be devoid of any objective referent, leading to the weakening of human rationality by presenting it as a feeble and inadequate tool for investigating the world objectively.
But between these two antithetical, symmetrical and mutually mirrored polarities there is a third theoretical possibility, one inaugurated, since its Greek origins, by the Socratic research, which seeks rather to pursue a different and much more complex representation of objective knowledge, which is not metaphysically absolute, even though it vindicates the opportunity to delineate some form of objective knowledge conceived as coinciding with the search for truth itself: a search, therefore, that, by its very nature, can never end.
Within this complex and labyrinthine interplay of knowledge, we must therefore change our traditional image of metaphysical knowledge, a la Socrates, by seeking to see the profound and even disturbing connections which always relate our knowledge to our ignorance. In fact, however much we may have undoubtedly increased, in the course of our history of human beings, our technical skills and knowledge, at the same time, as indeed was duly noted by Socrates, we have inevitably increased the knowledge of our own ignorance. Therefore knowledge and ignorance are not on oppositional and confrontational metaphysical horizons, precisely because they coexist and live together, always intertwined, on the same problematic horizon of our limping desire to know the world into which we have been cast. To better understand the critical subtlety of the sophisticated epistemological perspective inaugurated by Socrates, we can consider a sphere and imagine that its content matches overall our technical knowledge and skills, while its surface indicates the border area, i.e. that space, always moving and dynamic, which separates our knowledge from the scope of our own ignorance. Well, the increase in the overall volume of the sphere will mean, inevitably, the increase of our own ignorance, because knowledge and ignorance are two sides of the same coin, i.e. they are two components within which the very possibility of any increase of our though vague, but objective knowledge of the world is developed. So we can no longer think that knowledge and ignorance are two separate and clearly antithetical worlds, since the interplay in which we are involved is much more complex, because knowledge and ignorance mingle and intertwine constantly realising a composite reality of knowledge and technical skills within which knowledge turns up among error, but error too turns up among knowledge. Therefore we must be constantly vigilant to gather this complex interweaving critically, without ever attributing the status of absolute knowledge to this or that metaphysical alternative in a dilemma. Precisely because, as Socrates taught, the more we know, the more we become aware of our own ignorance...3