OK, so I failed to post numerous things last month. Evidently the summer is a challenging time for my blogging abilities. But, perhaps less is more.
Getting to the topic, I've been reading Anderson's (1985) Phonology in the Twentieth Century, and I'd like to highlight his description of the philosophical conflict between J. R. Firth's conception of phonology and that offered in the American generative paradigm spearheaded by Jakobson, and later Chomsky and Halle. Anderson characterizes the conflict as one between a realist philosophy of the American school, against a nominalist philosophy of the Firthian school.
Now, I don't want to specifically advocate for the Firthian paradigm in phonology, but when it comes to distinctive features in phonology, consider me a nominalist. Anderson describes nominalism as regarding the "idealizations of scientific theories simply as names for the analytic categories of the scientist," and to the extent that distinctive features are idealizations dreamt up by phonologists, I think the nominalist view is plainly correct.
On the other hand, according to Anderson "most empirical scientists, including linguists, tend to take a strongly realist attitude toward the essential elements of their theories." I don't know how uncontroversial such a claim about scientists is, but I personally feel it would be ludicrous to assert without specific evidence that a particular distinctive feature was in any sense "real." As a matter of fact, first you would have to specify in what way it was supposedly real, and then you would have to somehow prove that it was real in that sense (let's say, in a cognitive sense). Try it sometime! I don't believe there is any result that shows that any particular distinctive feature (not a phonetic feature mind you, but an abstract distinctive feature, let's say [+consonantal]) is cognitively real, and binary-valued, in the human mind.
So let's face it, when we discuss phonology, it makes more sense to be nominalists instead of realists. Realism is a kind of science-cum-religion that requires suspension of disbelief. Nominalism is purely analytical, without the extra baggage offered by realism. Why should a linguist care? Because whether you are a nominalist or a realist can affect what you would say about a variety of research projects. A nominalist would wholeheartedly support a project to, e.g., formulate a (possibly mathematical) theory of how binary or privative (i.e. unary) distinctive features appear to emerge from more specified phonetic features in the phonological systems of languages. Such a project would specifically examine how our analytical categories are founded in the detailed reality (as they ultimately must be). A realist, on the other hand, may be inclined to dismiss such a project because, after all, distinctive features aren't emergent properties, they're real, and so exist independently in a Platonic realm or something. Householder and Firth both caricatured this position as the "God's truth" view, that somehow if we could magically hit upon the right system of distinctive features, we would unearth God's truth.
But I also suggest that linguists keep the philosophizing to a bare minimum, just enough to sort out one's methodological position before deciding which projects might be worthwhile.