3.1. The social-linguistic models

In a very summarised way –simplified– we can display them as follows:

Table 1. The social-linguistic models

Source: Own elaboration.

We aimed to centre ourselves in three perspectives: The number of languages that the studies take care of, the number of facts, and the social paradigm to which are subscribed. In this way, we will have as many models as combined possibilities can be produced (27). We will pick out the most difficult one: The one that considers three languages, three facts, and that is inside the paradigm of social definition.

3.2. The juridical institution of the representation

Secondly, we thought that the description of the process of replacement could be improved if we reflected upon its similarities with the juridical institution of the representation. Let us see. Aracil (1983: 171-206) proposed the term of "insertion" that came to be a very good clarification. We realised that this concept came from the Law, and formed part of the juridical institution of the representation, were there has to be a represented, a representative, and a third. For example, the lawyers, the managers interpose between the represented people and the third, and they replace, precisely, these represented people. This structure is not only an analogy to those of linguistic replacement, but as well, they clearly show us the necessity to describe these proceedings and to give us a global perspective for it’s study (3).

3.3. The social representations

Thirdly, we checked if the theory of the social representation was suitable, especially elaborated by Moscovivi (1961, 1984), Doise (1986) and Jodelet (1989), to consider the replacement process from the concept that was missing to study what we named "perception" in the tertiary model of the table. We borrowed from this last social psychology the definition that proposes the social representation:

" Its a way of social acknowledgement that is elaborated and shared, that has a practical vision, and turns out in the construction of a common and whole social reality" Jodelet (1989: 36).

To say it in a plain (and inexact) way it would be the idea, the mental image that we make from what we know, for example, from the languages of our context. Certainly, this concept is near to the one of linguistic attitude, but much more complex, that it even includes it (4).

3.4. The etnolinguistic vitality theory

Next we tried to integrate the etnolinguistic vitality theory, like Giles, Bourhis and Taylor (1977), Allard (1984) and Landry and Allard (1988 and 1990) developed it in a wider frame of the theory from the social representations that we just commented at the previous point (5).

3.5. The catastrophe theory

Finally, we established a formal analogy with the mathematical catastrophe theory. It is not necessary to say that it is difficult to summarise all these proposals within the space of this article. If you are interested, you can consult Querol (1996 and 1999: 160-178 and 382-393). Otherwise, we will try to do a summary synthesis.

The analogy is fomented with the fact that the replacement processes are not regular, but sudden changes are produced. These discontinuities are the centre of the catastrophe theory, proposed by René Thom (1972, 1980a, 1980b and 1991) that tries to explain in which ways they can be produced. Let us see it in the following table: