text: The problem with classifying Kajkavian within South Slavic stems in part from its both structural differences and closesness with neighboring Chakavian and Shtokavian speeches as well as its historical closeness to Slovene speeches. Some Slavists maintain that when the separation of Western South Slavic speeches happened, they separated into five divergent groups — Slovene, Kajkavian, Chakavian, Western Shtokavian and Eastern Shtokavian, as a result of this, throughout history Kajkavian has often been categorized differently, either a node categorized together with Serbo-Croatian or Slovene. Furthermore, there do exist few old isoglosses that separate almost all Slovene speeches from all other Western South Slavic dialects, and do exist innovations exist common to Kajkavian, Chakavian, and Western Shtokavian that would separate them from Slovene. Croatian linguist Stjepan Ivšić has used Kajkavian vocabulary and accentuation, which significantly differs from that of Shtokavian, as evidence to be a language in its own right. Josip Silić, one of the main initiators behind the standardisation of Croatian, also regards Kajkavian as a distinct language by dint of its having significantly different morphology, syntax and phonology from the official Shtokavian-based standard. However, Silić's theorization about three languages and systems of Croatian, based on Ferdinand de Saussure and Eugenio Coșeriu concepts, is criticized for being exaggerated, incomprehensible and logically non-existent. According to Ranko Matasović, Kajkavian is equally Croatian as Chakavian and Shtokavian dialects. Mate Kapović notes that the dialects are practical and provisory linguistic inventions which should not be misunderstood and extrapolated outside the context of the dialect continuum.