William of Ockham (1285-1347) is the most famous so-called “nominalist” in Latin medieval philosophy. He sought to explain our practical and theoretical uses of universals entirely in terms of our relations to existing singular things.
Without losing sight of Plato’s emphasis on the value of pure thought, Aristotle had adopted a broader perspective, starting from the generality of human life. In this context, in contrast to Plato he had emphasized the genuine importance, positive role, and irreducibility of singular beings or things that we encounter in life. “For us” singular beings and things come first, even if they do not come first in the order of the cosmos.
Singular beings and things are more concretely “real” than any generalizations about them. But Aristotle simultaneously upheld the “Platonic” view that knowledge in the strong sense can apply only to generalizations of necessary consequences between things, and not to our experiences of singulars. There can be no necessity in our experience of something purely singular. What I would call the extraordinarily productive tension between Aristotle’s fundamental views of reality (putting singulars first) and of knowledge (putting universals first) created an appearance of paradox that later commentators sought to resolve, often by favoring one side at the expense of the other.
Ockham wanted to explain universals entirely in terms of singulars. In the Cambridge Companion to Ockham, Claude Panaccio summarizes that “Ockham’s project is to explicate all semantical and epistemological features — truth values, for instance — in terms of relations between sign-tokens and singular objects in the world” (p. 58).
Ockham built on the work of many less well-known figures. The Latin world had seen lively inquiries about logic and semantics since the 12th century, when Arabic learning first began to be disseminated across Europe. Within this tradition, there is more than one approach to meaning.
The technical notion of “signification” was a development inspired largely by Augustine’s theory of “signs”. Unlike more recent usages (e.g., in Saussurean linguistics), this kind of signification involves a simple relation of correspondence between a thing taken as a “sign” and some other thing.
Ockham and many of his predecessors held that there is such a thing as natural signification, independent of any language. In this sense, smoke is taken to be a “sign” of a fire. This relation of smoke signifying fire is called “natural”, because in our experience smoke only exists where there is fire, and this has to do with how the world is, rather than with us. This is very different from the conventional imposition of the word “fire” to refer to a fire.
At the same time, this notion of signification also seems to have an irreducible “psychological” component. It has something to do with how the world is, but in a more direct sense, it has to do with something like what the British empiricists later called the association of ideas. Our “natural” association of smoke with fire is not arbitrary. As the empiricists would say, it is grounded in experience. As the Latin scholastics would say, the soul “naturally” tends to associate smoke with fire, and this is as much a truth about the soul — or about the soul existing in the world — as it is a truth about the world.
For Ockham, natural signification applies to concepts, which constitute the core of a sort of “mental language” that is in many ways analogous to spoken or written language, but is more original and does not depend on convention. Concepts on this understanding are subject to all the same kinds of syntactical relationships as individual words in speech.
In this tradition, the meaning of concepts is analyzed by analogy with the role of individual words in speech. This presupposes a view that linguistic meaning overall is founded on the meanings of individual words. The individual concepts of “mental language” that apply to individual real-world things are analogously supposed to have pre-given, natural meanings. Logic and semantics are then a sort of mental hygiene with respect to their proper use.
Ockham offers a rich analysis of connotative terms that modify the concepts corresponding to things.
Again building on the work of many authors in the Latin tradition, he develops the theory of logical “supposition”, which contemporary scholars associate with semantic discussions of reference to real-world objects. This has nothing to do with supposition in the sense of hypothesis; rather, it relates etymologically to a notion of something “standing under” something else.
Notably, Ockham and this whole tradition insist that while individual words independently have signification, only in the context of propositions or assertions expressed by whole sentences do words have the kind of reference associated with supposition. I suspect this is ultimately grounded in Aristotle’s thesis that truth and falsity apply only to whole propositions or assertions; “supposition” is to explain not just meaning, but also truth and falsity. This tradition develops a much more explicit theory of reference than Aristotle did, and the kind of reference it develops is tied to contexts of assertion, or true assertion.
The idea that reference to real-world things should be approached at the level of propositions rather than individual words or concepts has much to recommend it. But for Ockham and the tradition he continued, supposition is still fundamentally governed by signification, and signification begins with individual words or concepts. Individual words or concepts are thought to have pre-given meanings, and Ockham attempts to give this a theoretical grounding with his notion of “mental language”.
As Ockham suggests, there is a way in which notions of syntactic relations apply to pure concepts. But I take this to be an abstraction from actual usage in spoken or written language, and I don’t believe in any pre-given meanings.
Ockham’s general strong privileging of individual things over universals has a deep relation to his voluntarist and fideist theology, which owes much to his fellow Franciscan Duns Scotus. In logic, Scotus is considered a defender of “realism” about universals as opposed to nominalism, but in his theology he developed a strong notion of individuation, tied to a very radical notion of divine omnipotence that refused to subordinate it in any way, even to divine goodness (see Aquinas and Scotus on Power; Being and Representation). Essentially, from this point of view, every single thing that happens is a miracle coming directly from God, and all observed regularity in the world pertains only to a sort of divine “habit” that could be contravened at any moment.
Aquinas aimed at a sort of diplomatic compromise between this extreme theistic view that makes everything solely dependent on God, and Aristotle’s unequivocal assertion of the reality of “secondary” causes. Scotus and Ockham applied high levels of logical sophistication in defense of the extreme view.
Ockham also denied the reality of mathematical objects. Together with his extreme view on divine power, this makes very unlikely the view promoted by some scholars that Ockham in particular represented the strand of medieval thought that most helped promote the emergence of modern science. Ockham’s undeniable logical acumen was dedicated to downplaying rather than elaborating the practical importance of order in nature.
It does seem, though, that views like Ockham’s contributed to the shaping of British empiricist philosophy. Here is another chapter in the complex history of notions of reference and representation. Ockham’s very strong notion of reference as directly grounded in singular real-world objects — combined with that of the natural signification or pre-given meaning of concepts in “mental language” — helped lay the ground for what modern empiricism would treat as common sense.
For most of the 20th century, the mainstream of analytic philosophy seemed to be inseparable from a strongly empiricist direction. But Wittgenstein, Quine, Sellars, Brandom, and others have initiated a new questioning of the assumptions of empiricism from within contemporary analytic philosophy. Analytic philosophy is no longer nearly so opposed to the history of philosophy or to continental philosophy as it was once assumed to be. It is in this context that we can begin to look at a sort of Foucaultian or de Libera-esque “archaeology” of empiricism, in which Ockham certainly deserves an important place.