The distinct separation between logics and application that L. J. E. Brouwer, the founder of logical mathematical intuitionism was pleading for in the beginning of the 50's should be seen with reserve today. Nowadays logic is more and more linked to the context of applicatory researches, leaving at least, for a while the undesirable status of "wandering son" that it was sometimes associated to and returning to the noble destiny the Greek antiquity had invested it: that of organon, i.e. instrument of knowledge. This attempt is an applying of the logical instrument to the analysis of education and educational language. There is no doubt that educational language has certain characteristics that ensure its own way of manifestation among the multitude of discourse types. What should be these characteristics, what semiotic, logical or rhetoric mechanisms, what effects of such a language upon the audience should be and how they should diversify in discursive educational practice are some questions we are trying to find an answer.

The analysis of the connection between logic and education is trying to elaborate some operational practical criteria scientifically proved for the delimitation of the different categories of educational acts. We give a special significance to the concept of educative intervention which is based on a semio-logical interpretation of the educative act. Educative intervention is considered to be a communicative structure, discursive or not, that its message being understood by the audience, produces modifications in human personality, in form and with different intensities. Defining this concept that projects the praxiological dimension of education gives way to another attempt that seems to be unique in this field: the systematization of the types of educative intervention. The basic criterion for this systematization begins with the analysis of the communication relation essential in any educative intervention.

Educative intervention typology has a logical foundation. A scientific statement can be sustained and proved only when it has a rational support. This support is concrete in three types of logic of educative interventions: logic of affectivity (which is fundamental for self-educative intervention), logic of authority (which sustains educative intervention) and social logic (basis of educative intervention through "community mentalities"). The systematization of types of educative logic also is useful for another purpose: the structuring of metaeducational discourse using the criterion of educative logic. Thus a link is established between affectivity logic and the doctrine of ''new education'', between authority logic and what is usually known as ''traditionalist vision'' on education, between social logic and some tendencies such as ''axiological education'' and ''social education".

The restriction of the analysis educative interventions to the facts achieved by using educational language leads to a three-dimensional model of language by revaluation of semiotical logical and rhetorical perspective. We have tried to give an answer to the following questions that are essential for denoting the specificity of this type of language: which is the communicative support of the educative intervention? (i.e. the sign system and the communicative ability of the ''actors'' of the education relation), which is the logical-rational support of the interventions? (i.e. logical operation and their combinatory and structural modalities in educational discourse) and which is the performative support of the intervention? (rhetorical operations and proceedings that may occur during such a discourse).

The semiotical considerations on educational language lead to the following conclusions : a) the concept of educational language may be sustained as distinctive form of natural language by using a proper definition from the actionalist semiotics area where the stress is on the influentional relation between the sign system and the personality of the receiver; b) from the semiotical model perspective suggested at the level of the discourse units so-called phrastics (small units at the sentence level) the educational language is not different from the other types of languages (scientific, political, metaphysical) and thus the common trunk of the natural language it is obvious; c) differences may appear on the level of transphrastic ascriptors and they find their explanation in the combination between dominant signs (that give the tonality of a discourse) and the dominate signs (that are subordinate to the former ones and contribute to the fulfillment of their purpose); d) in the area of educational language the prescriptors are the main signs, or more precisely, the educational language is predominantly prescriptive from the perspective point of view and predominantly appreciative from the perspective of the modalities of ''putting into shape''.

This investigation of the educational language as a system of discursive segments is to be followed by another one that should discuss the same language as segments of knowledge acts. This point of view is taken into account by the logical analysis of educational language that regards the problem of logical inner structures, their logical characteristics that ensure the performative character of educative discursive interventions. The problem here is that of the alethic value of the discursive segments that are components of educational language, values from a "logic of nuances'' with proper linguistic expression ("very true", "true enough'', "more or less true''). The gradation of the truth values in such a language will have some effects on the deductive processes, making a syllogistics with distinctive characteristics in the discursive area. Logical exigency of such a discourse does not agree with the presence of contradictory enunciation, ambiguity manifestations and message distortions in communicative act.

The third point of the analysis of the educational discourse is that of the level of rhetorical dimension. There are two aspects we should take into account: rhetorical perlocutive proceedings in a discursive intervention and the role of the metaphorical language in educational discourse. Among the rhetorical proceedings we name the discursive slogan, comic intervention and ironic intervention. The analysis of these proceeding is well-come as there aren't pertinent and comprehensive analyses about their performative role in the discourse. On the other hand, the rhetorical environment where the educational discourse is placing the audience gives it a certain distinction, gets it out of platitude and banality and puts it in the area of Nietzschean discourse where ''to say'' means ''to do''.

Educational discourse can cover various forms. We try to make an investigation of the educational language hypostases using the three-dimensional model (semiotical, logical, and rhetorical). We should consider three hypostases significant from our point of view: argumentative discourse, demonstrative discourse and explicative discourse. Although these discursive forms have got common characteristics (underlying the concept of educational language in which everybody takes part) they are different in the dominant discursive tonality and this ensures their part in discursive act.

Considering the argumentative discourse hypostasis we suggest a semiological model of argumentative intervention that should take in account the three levels of analysis and interpretation of the educational discourse: logical level (i.e. the internal logic of an argumentative discourse), semiotical level (i.e. the semantic dimension of an argumentative intervention, meaning the role and functions of the topic reference of the discourse) and rhetorical level (i.e. the performative mechanisms of argumentative intervention and efficiency of these rules in discursive poetics). Methodologically and epistemologically dissociated, these three plans of analysis manifest themselves in close interrelation and contribute to the "creation'' of intentionality of any argumentative discourse: conviction and persuasion of the audience.

The considerations on the internal logic of the argumentative discourse have the starting point in G. Vignaux's pertinent analyses concerning the concept of "discursive logic". ''Argumentative logic" as discursive logic comprises two categories of operations: discursive operations (which are more related to the discourse area and are characterized by rules of correct rationality) and metadiscursive operations (that are linked by subject and are entirely new among the logical analyses). Semantic analysis of argumentative discourse has in view two concepts: discursive schematizing and argumentative schematizing, either of them concerning the brief but essential image of topic reference of a discourse in general or of an argumentative discourse in particular. The new element of the rhetoric analysis included in context of argumentative discourse investigation refers to the discovering, analyzing and exemplifying of some pragmatic rules of argumentative performance.

The second hypostasis of educational language is the demonstrative discourse. It is reported to the same matrix of interpretation, thus delimitating the logical structure of the demonstrative intervention and the functionality of discursive schematizing of demonstrative type and its manifestations in rhetoric area. Starting from Aristotle's observations in Second Analytics we notice their actuality and continuity in the most important realizations of the last century: axiomatic and formalized systems of logic and mathematics. The conclusion of these analyses is that the logic structure of demonstrative intervention are deductive i.e. they always reach the necessary conclusions. The aspect is not only in the area of rigorous constructions such as axiomatic systems, but in ordinary demonstrations in the area of didactic activities at different subjects.

Demonstrative schematizing is different from argumentative one because they do not associate to the image on discourse theme but on logical assumption used for passing from a demonstrative segment to the other. The developments in the area of rhetoric dimension of the demonstrative discourse are made with some precautions. The first one materialized in fundamenting of two types of rhetoric: a cognitive and a rhetoric one. This classification is due to the kantian distinction between conviction and persuasion. The second precaution makes us think of the determinant role of cognitive rhetoric i.e. rationality mechanisms. The mechanisms of aesthetic rhetoric when they manifest themselves have in view the preparation of a special audience to whom a demonstrative intervention is addressing.

The final stop in the area of the educational language forms is taking into account the explicative discourse. There are two attempts concerning the logical structure of explanation: E. Meyerson's based on the identification relation and C. Hempel's known as the deductive-nomological model based in sufficient-necessary conditioning relation between explanans and explanandum. The analysis of scientific explanation structure is necessary for our proposition concerning our scientific research: i.e. the imposing of the concept of educational explanation as the only type of explanation that acts as cognitive intervention on the listener. The investigation of the semantic dimension of the educational explanation tries to find an answer to the following question: What are the discursivity mechanisms used as a link between scientific explanation to the educational one? The answer analyses the way of structuring the explicative discursive schematizings and their impact to the audience. The final attempt concerning metaexplicative discourse stresses on the obtained performances. They are achieved both in cognitive rhetoric and aesthetic rhetoric area for the fulfillment of the same aim: the understanding of the given fact.

Our attempt whose results are to be put to critical judgment is bound to a deductive order. It goes in an extensional decrescendo from the analysis of educative intervention (a concept with a large area) to the "destructuring of discursive educative interventions (i.e. species of the former ones materialized in the interventions through educational language) and delimitation of the forms of educative discursive interventions (i.e., "species of species" such as argumentations, demonstrations and explanations). It concerns a cognitive equilibrium between the directly involved domains, logic and education, one with methodological-applicative vocation, the other one being a perfect area for revaluating this vocation.