‘Simplicity’ and Linguistics

I was happily re-reading this excellent introduction to Linguistics this evening, when I stumbled across a sentence that annoyed me.

‘Obviously, [example X] is consistent with general scientific guidelines which require us to always seek the simplest and most elegant theory which is consistent with the data we need to explain.’ (Radford et al., 1999:330)

I’ve found that this kind of sentiment is so common in Linguistics that people barely mention it. Indeed, you might have read the above quotation and thought, yes, obviously. The idea is clearly influenced by Occam’s razor, which Wikipedia sums up as ‘a principle that generally recommends that, from among competing hypotheses, selecting the one that makes the fewest new assumptions usually provides the correct one, and that the simplest explanation will be the most plausible until evidence is presented to prove it false.’ Apparently, the principle is attributed to William of Ockham, hence the name. I think that this principle is so deeply embedded in our understanding of the world that most of us have never really thought about it. I must confess, when I started to notice I’d accepted this principle without thinking about why, I started to find it deeply dissatisfying. Who says that the hypothesis which makes the fewest new assumptions usually provides the correct one? What evidence is there of this? What governs this principle? Is it not more of a methodological suggestion of how to test theories, rather than an existential fact about stuff? The only times I have ever seen Occam’s razor discussed in any discipline is when it is appealed to as a kind of universal law which is assumed – obviously – to be true. I’m not necessarily saying I think it’s not true, just that very few people (in syntax at least) seem to challenge this assumption, something which has pervaded linguistic thought for a long time and which has reached its peak in the Chomskyan tradition.

Indeed, the Minimalist Program, which is currently the most fashionable theory of syntax, is underpinned by this principle, and this is implicit in its name. The following extract comes from an introductory textbook to the theory.

‘As in any other domain of scientific inquiry, proposals in linguistics are evaluated along several dimensions: naturalness, parsimony, simplicity, elegance […] etc. […] Put another way, the task is to find a way of taking the platitude that simpler, more elegant, more natural theories are best and giving them some empirical bite.’ (Hornstein et al., 2005:5-6)

Later, the authors introduce a caveat:

‘It’s possible that the language faculty is just “ugly”, “inelegant”, “profligate”, “unnatural” and massively redundant. If so, the minimalist project will fail. However, one can’t know if this is so before one tries. And, of course, if the program proves successful, the next question is why the language faculty has properties such as elegance and parsimony.’ (ibid., 7)

Am I the only one who thinks basing a whole research program around nothing more than a nice idea is a bit strange?

Naturally, the whole issue is underpinned by the question of whether the language faculty is ‘natural’, ‘parsimonious’, ‘simple’ or ‘elegant’. The first problem we have is that it is not abundantly clear what these terms actually mean with regards to language. I’ve come across few people who have attempted to explain what they mean by such terms. Usually linguists just use the terms as a sort of theoretical dustbin into which they shove any possible counterargument to their particular theory, because stating that one’s theory is more ‘simple’/’elegant’ is akin to trumping anyone’s ace.

If the language faculty is ‘simple’/’elegant’/etc. (and here we are presupposing that there is a language faculty of some sort), the only way we can access it is through the linguistic performance of a speaker, clearly. If the linguistic performance of a speaker is ‘simple’, then I might be able to be persuaded that his/her linguistic competence is ‘simple’. I would find it highly dubious if someone made the claim that linguistic performance is messy, but linguistic competence is not, as one cannot directly access the latter. What do others think?

As it happens, I’ve yet to be convinced that language (in the sense of performance) is simple, elegant, or parsimonious. If it were, why would we have to bend over backwards accounting for things in a complex way theoretically? Take plural formation as a banal example. In English, it’s nice and simple. You have your lexeme (word) in your lexicon (mental dictionary), e.g. book. To make a plural, you just whack on the suffix -s. That seems like a fairly straightforward default rule. If I asked you what the plural of gallyhop was, you’d say gallyhops, even though I can guarantee you’ve never heard the term gallyhop before and you have no idea what one is. Yes, there are exceptions like children and sheep, but we can account for those by listing them separately in the lexicon. But look at German. There are eight ways of forming the plural. If there is a ‘default’ way, which one is it? And how do we account for the other seven ways? Surely employing eight methods of forming the plural is hardly ‘simple’, ‘elegant’ or ‘parsimonious’?

It was put to me a while ago by one of my professors that the idea of the language faculty needing to be maximally simple might have had more to do with what computers could do at the time the idea came about than with what the language faculty can do. As little as twenty years ago, computers could store very little. I suppose it’s not surprising that one might think that storing information requires an inordinately large amount of space, and thus theoretical concerns were formed accordingly. Does anyone have any views on this?

References:

Radford, Andrew, Martin Atkinson, David Britain, Harald Clahsen, and Andrew Spencer. 1999. Linguistics: An Introduction. Cambridge University Press, Cambridge.

Hornstein, Norbert, Jairo Nunes and Kleanthes K. Grohmann. 2005. Understanding Minimalism. Cambridge: Cambridge University Press