Approaches to style changes are discussed here as a problem of a textologically founded theory of the history of literary style, namely: (1) literary works, components of literary style, are texts, (2) their relations, intertextuality, its dynamism offers one of the possibilities of understanding style change, (3) literary style as well as one of its historical components, style tendency are conceived of as supertext categories, (4) the immediate source of a diachronic textological theory is 'historicity' of texts. The whole theory, as well as, the general framework within which our discussion proceeds are discussed in SZABÓ (1982., 1985., 1988., 1992., 1995.; see the former list of references).

The main procedural category of the history of literary style is ’style tendency’, in a way equivalent to ’literary trend’ (movement, school or, maybe, era). It serves for dividing literary style along diachronic lines. The approach of style tendencies implies both synchronic and diachronic dimensions. At the synchronic level the inquiry is structure-centred whereas at the diachronic level it is succession-centred. Successive tendencies – described as synchronic ’cust’ – are compared and the differences which can be noted are conceived of as outcomes of changes.

As a matter of fact, changes must be viewed not merely as objects of observation, but as objects of explanation, too. The researcher cannot stop at revealing shifts, he also must be concerned with their causes. As for these causes we have to be aware of the fact that we cannot attempt an approach along the lines of – say – physics, chemistry, since style – or in general human events – do not follow laws in that sense, they have their own properties that must not be overlooked. That is why we cannot seek what is termed ’internal laws’ (at least not today), but only simple explanations of changes.

Components of explanations may be of external and internal character. Constituents of external conditioning are mainly socio-historical, cultural factors, including pragmatic ones, too, which are well-known facts of literary history. The main internal explanations are: (1) antithesis and its collateral, cyclism (recurrency), (2) dynamism resulting from intertextual relations and which may bear on transtextuality. Explanation based on external and internal conditioning are to be considered as historically interacting reasons. Tehir mutual relations may strengthen their explanatory adequacy. As for the explanatory adequacy of the discussed possibilities we have to admit that they have a limit. That is why I also admit that everything I have argued here is a matter in dispute: the issue is still an open question.