Quinean ontological commitment and properties

Question

Take the following sentence: Some students are brilliant.

According to Quine, is this sentence ontologically committed to things students and to the property brilliance or being brilliant? From what I understand, Quine doesn't want to commit to properties. Wouldn't he still commit to properties in this example? If not, what is this sentence committing to, then?

See Quine: Metaphysical Claims: "his ontology consists of physical objects and sets. [...] Quine does not accept the existence of any abstract objects apart from sets. His ontology thus excludes other alleged abstracta, such as properties, propositions (as distinct from sentences), and merely possible entities." — Mauro ALLEGRANZA, Dec 11 '23 at 14:48
I think that, to get ontological commitment, you have to quantify over something in a sentence. Quine was willing to commit to some degree of mathematical realism because he was willing to quantify over some mathematical objects. By contrast, in the given sentence, we are quantifying over students only, not brilliance too, ergo... — Kristian Berry, Dec 11 '23 at 14:49
See Properties : "Quine (1957) contrasts the “murky intensionality of attributes” to the “limpid extensionality of classes” and speaks of all intensional entities as “creatures of darkness” (1956)." — Mauro ALLEGRANZA, Dec 11 '23 at 14:54
And see Peter Geach, Quine on Classes and Properties (The Philosophical Review, 1953) — Mauro ALLEGRANZA, Dec 11 '23 at 15:21
Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking. — Community, Dec 11 '23 at 17:12

Mauro ALLEGRANZA · Answer 1 · 2023-12-12T09:34:10.877

See Willard Van Orman Quine, Confessions of a Confirmed Extensionalist and Other Essays (Dagfinn Follesdal editor, Harvard UP 2008), Ch.1 Nominalism (1946), page 11:

So nominalism is distinct from the doctrine known in modern logic as extensionalism. The main point of the latter doctrine is rejection of properties, or attributes, in favor of classes. But classes are universals equally with attributes, and nominalism in the defined sense rejects both. The fact that classes are universals is something obscured by calling them “mere aggregates”, and feeling that this likens them to heaps, which are indeed particular. A heap of stones is a particular, bigger than but no less particular and concrete than any single stone which occurs in it as a part. But the class of stones in the heap cannot be identified with the heap.

For, if it could, then by the same token the class of molecules of stones in the heap could be identified with the heap; and then there would be no distinguishing between the two classes. This would be unacceptable, since we want to say that the one class has some 150 members while the other has some trillions.

In conclusion, regarding the sentence "Some students are brilliant", Quine would be committed to the existence of the class of brilliant things.

According to well-known Quinean criteria ("to be is to be a value of a variable"), to be committed to the existence of properties amounts to adopt second-order quantification. But for Quine [Philosophy of Logic, 1970], second-order logic is “set theory in sheep’s clothing”.

score 1 · Answer 2 · answered Dec 11 '23 at 22:46

Quine might've been willing to paraphrase this as, "Some students are in the set of brilliant beings," and keeping tight the quantification-extension connection, this would have him committing to students and sets, but not brilliance as a property. For further discussion with an emphasis on Quineanism, see the two sections in the SEP article on ontological commitment that address interpretations of Quine: the first has an extensionality-theoretic focus, the second has a metalanguage-theoretic focus. For a somewhat more general assessment of the question of ontological commitment to properties, see this quotation of sec. 1.7.1.:

Quinean ontological commitment and properties

2 Answers2