Chomsky & Katz (1974) on language diversity

Chomsky and others, Stich asserts do not really study a broad range of languages in attempting to construct theories about universal grammatical structure and language acquisition, but merely speculate on the basis of “a single language, or at best a few closely related languages” (814). Stich’s assertion is both false and irrelevant. Transformational grammarians have investigated languages drawn from a wide range of unrelated language families. But this is beside the point, since even if Stich were right in saying that all but a few closely related languages have been neglected by transformational grammarians, this would imply only that they ought to get busy studying less closely related languages, not that there is some problem in relating grammar construction to the study of linguistic universals. (Chomsky & Katz 1974:361)

References

Chomsky, N. and Katz, G. 1974. What the linguist is talking about. Journal of Philosophy 71(2): 347-367.

Another quote from Ludlow

Indeed, when we look at other sciences, in nearly every case, the best theory is arguably not the one that reduces the number of components from four to three, but rather the theory that allows for the simplest calculations and greatest ease of use. This flies in the face of the standard stories we are told about the history of science. […] This way of viewing simplicity requires a shift in our thinking. It requires that we see simplicity criteria as having not so much to do with the natural properties of the world, as they have to do with the limits of us as investigators, and with the kinds of theories that simplify the arduous task of scientific theorizing for us. This is not to say that we cannot be scientific realists; we may very well suppose that our scientific theories approximate the actual structure of reality. It is to say, however, that barring some argument that “reality” is simple, or eschews machinery, etc., we cannot suppose that there is a genuine notion of simplicity apart from the notion of “simple for us to use.” […] Even if, for metaphysical reasons, we supposed that reality must be fundamentally simple, every science (with the possible exception of physics) is so far from closing the book on its domain it would be silly to think that simplicity (in the absolute sense) must govern our theories on the way to completion. Whitehead (1955, 163) underlined just such a point.

Nature appears as a complex system whose factors are dimly discerned by us. But, as I ask you, Is not this the very truth? Should we not distrust the jaunty assurance with which every age prides itself that it at last has hit upon the ultimate concepts in which all that happens can be formulated. The aim of science is to seek the simplest explanations of complex facts. We are apt to fall into the error of thinking that the facts are simple because simplicity is the goal of our quest. The guiding motto in the life of every natural philosopher should be, Seek simplicity and distrust it.

(Ludlow 2011:158-160)

References

Ludlow, P. 2011. The Philosophy of Generative Grammar. Oxford University Press.
Whitehead, W. N. 1955. The Concept of Nature. Cambridge University Press.

A page from Ludlow (2011)

Much writing in linguistic theory appears to be driven by a certain common wisdom, which is that the simplest theory either is the most aesthetically elegant or has the fewest components, or that it is the theory that eschews extra conceptual resources. This common wisdom is reflected in a 1972 paper by Paul Postal entitled “The Best Theory,” which appeals to simplicity criteria for support of a particular linguistic proposal. A lot of linguists would wholeheartedly endorse Postal’s remark (pp. 137–138) that, “[w]ith everything held constant, one must always pick as the preferable theory that proposal which is most restricted conceptually and most constrained in the theoretical machinery it offers.”

This claim may seem pretty intuitive, but it stands in need of clarification, and once clarified, the claim is much less intuitive, if not obviously false. As an alternative, I will propose that genuine simplicity criteria should not involve appeal to theoretical machinery, but rather a notion of simplicity in the sense of “simplicity of use”. That is, simplicity is not a genuine property of the object of investigation (whether construed as the human language faculty or something else), but is rather a property that is entirely relative to the investigator, and turns on the kinds of elements that the investigator finds perspicuous and “user friendly.”

Let’s begin by considering Postal’s thesis that the simplest (and other things being equal the best) theory is the one that utilizes less theoretical machinery. It may seem natural to talk about “theoretical machinery,” but what exactly is theoretical machinery? Consider the following questions that arise in cross-theoretical evaluation of linguistic theories of the sort discussed in Chapter 1. Is a level of linguistic representation part of the machinery? How about a transformation? A constraint on movement? A principle of binding theory? A feature? How about an algorithm that maps from level to level, or that allows us to dispense with levels of representation altogether? These questions are not trivial, nor are they easy to answer. Worse, there may be no theory neutral way of answering them.

The problem is that ‘machinery’ can be defined any way we choose. The machinery might include levels of representation, but then again it might not (one might hold that the machinery delivers the level of representation, but that the level of representation itself is not part of the machinery). Alternatively, one might argue that levels of representation are part of the machinery (as they are supported by data structures of some sort), but that the mapping algorithms which generate the levels of representation are not (as they never have concrete realization). Likewise one might argue that constraints on movement are part of the machinery (since they constrain other portions of the machinery), or one might argue that they are not (since they never have concrete realizations).

Even if we could agree on what counts as part of the machinery, we immediately encounter the question of how one measures whether one element or another represents more machinery. Within a particular well-defined theory it makes perfect sense to offer objective criteria for measuring the simplicity of the theoretical machinery, but measurement across theories is quite another matter. (Ludlow 2011: 153)

References

Ludlow, P. 2011. The Philosophy of Generative Grammar. Oxford University Press.
Postal, P. 1972. The best theory. In S. Peters (ed.), Goals of Linguistic Theory., pages 131-179. Prentice-Hall.