William of Ockham
William of Ockham (Ockham, about 20 km far from London, 1280 – Munich, 1349) was the first antimetaphysician, although he was slightly anticipated by Petrus Aureolus (1280-1322), who however remained a philosophical personality of minor importance. With William the “lay” spirit is born, that is a way of self-perceiving free from faith and from the Church. To him faith and reason do not harmonize naturally, as Thomas Aquinas had believed; the truths of faith, unlike what we have seen in Saint Anselm and Saint Thomas, can in no way be an object of rational demonstration and therefore are not part of the knowledge, of the research fields where philosophy is concerned. Similarly, about politics, Ockham denies that the power of the emperor must depend on that of the pope; but, according to him, even within the Church the pope has to be considered a minister, rather than a ruler. The truths of faith must not be defined by the pope, or by the council, but by the church, conceived as a free community of the faithful. Therefore many of William’s theses were condemned by the pope and in 1328 he had to flee from Avignon (a city in the south of France), to take refuge by the emperor Louis the Bavarian, who was temporarily in Pisa, and then continue to follow him to Munich of Bavaria.
In 1852 Sir William Rowan Hamilton (1805-1865) created the expression “Ockham’s razor” to indicate the criterion defined by William of Ockham, according to which we must not multiply the entities if it is not necessary; that is, we must not work by imagination, inventing the existence of entities of any kind, just because we need to find an explanation for something; the explanation of phenomena must be sought striving to resort to the simplest and elementary hypotheses possible, rather than arbitrarily increasing the number of factors with the introduction of the real existence of abstract things. We can make a comparison, for example, with the way today some people try to explain UFOs, or other phenomena that seem a bit strange, by easily introducing the idea of the existence of unknown entities, such as Martians or ghosts; the additional factors invented do nothing but further complicate the issues, since they hypothesize the additional existence of other beings, who in turn will then need further explanations. If, for example, we want to explain how an object went from position A to position B, according to William of Ockham we should not invent a third being C, a third hypostasis, which is called movement; we can talk about movement, but while remembering that it is not a being, a reality, but only a name we give to our particular way of experiencing an object. In this context, William of Ockham also states that there is no reason to conceive the celestial world as having a nature different from the one trampled by our feet.
His anti-metaphysics, therefore, means a refusal to attribute real consistency to universal categories; he denies Plato’s world of ideas, as well as Aristotle’s substances or essences; abstract concepts should be treated instead as pure verbal instruments, as pure names (William is the first “nominalist”), indicative of a probable knowledge, and not as essences having an existence by themselves, distinct from particular objects; the latter, in their fragmentary nature, their multiplicity, are the only thing that actually exists. Consequently, logic, from being Aristotelian, that is, from reasoning about real things, is converted into logic of names, of the functioning of parts of speech, thus anticipating the disciplines that today are called syntactic, semantic, semiotic analysis. The anti-metaphysics of William of Ockham can be considered “moderate”: he takes a step forward, criticizing the idea of the autonomous existence of universal concepts, but he recognizes reality to the single objects that fall under our senses and create our experience. Later, Heidegger (1889-1976) will make the definitive transition to an anti-metaphysics that completely puts aside the question of the attribution of reality even to objects, as it is unreachable, and will adopt the term “metaphysics” to designate rather the sense of human existence.