Dispersion is an important process in language evolution. The presence, throughout a human population, of tokens of any particular linguistic type inevitably involves some process of dispersion. Dispersion is a dynamical process that describes change of a kind. One principal instrument of dispersion is constituted by the processes by which children newly acquire language. Another important example is how technologically inspired neologisms, fashionable inventions and rediscoveries, and other linguistic innovations, such as slang and colloquial modifications, also become dispersed among the linguistic repertoires of adult or other sub-populations.
In the course of dispersion change is inevitable. In the first place, even in the case of nouns and adjectives, individual language users can acquire slightly different extensional biases and preconceptions. These will be inherited, again in slightly altered form, by further language users who acquire the use from others.
Dispersion multiplies the instances of a specific vocable, that is, this vocable will gain increasingly slightly different uses, over time, as it is uttered in an increasing number of linguistic transactions.
The English word internecine provides an example of this purely extensional alteration.4.1
Any in English interrogatives has free-standing existential import as; Do you have any siblings? But it also has universal import in certain affirmatives where it is mostly restricted to negative and modal constructions. (Compare I have not read any of these books with I have read any of these books or You may have any soft beverage with You have any soft beverage.). Such divergences are occasioned by specific and kinds of schisms in human speech, in which one party of language users understands a word differently, but undetectedly so, from some other party. But the mere use of such vocabulary as adjectives, adverbs, nouns and verbs increases what could be called their actual extension. An actual extension is the class of things or n-tuples of things to which they have actually been applied by speakers of the language. That modification, to a standard definition of extension, alters the circumstances under which linguistic descendants receive the vocabulary. Usually, the extension of the relation of a particular vocable will only include one class of items such as nouns or adjectives or verbs, and so on. The actual extension can potentially include all of those and more. We will explain further in the section about attenuation.
Overwhelmingly, the tendency of these changes is toward a relaxation of earlier inhibiting controls on the uses of vocabulary.
Specializations as well as generalizations, in vocables, can be products of the kind of relaxation we have in mind. Consider, for example, the word fond. The loss of inhibiting controls represents as well a loss of capacity to have particular sorts of effect of fond to create an expectation of foolishness, even in connection with the object in respect of which fondness is attributed.
Early on, fond, in its use, was akin to the current use of crazy. To have a fond hope is an expression that is seldom used, mostly because fond has been restricted to another kind of syntactic structure such as fond of someone. In fact crazy over replaced fond of in generating the kind of emotive effects that fond used to produce. To be crazy over or about someone does not suggest psychopathology as: This person was institutionalized because he is crazy does. Crazy over is a eccentric use of the word in an effort to convey strong feelings for someone or something. In this case crazy is not meant as a disorder but rather as an occasion of a mild form of the original inferential effects. Unlike fond, crazy has retained its original use for now. We might assume that crazy will suffer a fate similar to that of fond; that is, the use of fond as shifted from one syntactic form to an other, while slowly shedding the original use. Fond is further along in the widening of its extension, more specifically, it has undergone a narrowing of use through the widening of its extensions. Statistically, some instances of fond have been discarded while other have survived. These instances are often relaxed uses. That is, the core use has been lost, while the eccentric use becomes the norm. The extension of fond is thus altered.
The loss of extensions is the basic dynamics at the root of language evolution. These examples illustrate a tendency for individual vocables to evolve towards a point of transformation wherein extensions slowly disappear from a conversational use of language until all instances of a vocable no longer generate any of the early effects.
One of the consequences of the loss of extension is the functionalization of vocables from lexical uses. We pose the question: What is the use of functionalized vocabulary?
Vocables may disappear from the language or they may change in structure; that is, they may transform from the sort of vocables that we understand readily and use accordingly, to the sort that is not well understood and used expertly nonetheless. To be more specific, the extension of a vocable is a gradient of instances that ranges, early on, from lexical uses entrenched in perceptual cues to instances that, later on, may become very abstract, even vague, and in extreme cases become functionalized uses. Functionalized uses are those of which early extensions have been forgotten and take on almost purely syntactic roles.
As explained in Chapter two, functional vocabulary descends from lexical vocabulary. The distinction may not seem dramatic; however a consistent semantic theory of functional vocabulary has evaded philosophers of language. As we have mentioned in the introduction, Philosophers' semantic accounts of functional vocabulary differ widely and there doesn't seem to be much consensus. However they seem to agree that lexical vocabulary is semantically difficult while a semantic for functional vocabulary seems more available. We think that the reverse is more likely. Lexical vocabulary is more readily definable when we inquire about its use, casually in a conversation. In the history of vocables, it is the functionalized instances of some vocables that seem to lose the capacity to be well understood. So the question remain, why do we have functionalized vocabulary? And how do we use it?