text: In general, the issue of the nature of proto-language remains unresolved, with linguists generally taking either the realist or the abstractionist position. Even the widely studied proto-languages, such as Proto-Indo-European, have drawn criticism for being outliers typologically with respect to the reconstructed phonemic inventory. The alternatives such as glottalic theory, despite representing a typologically less rare system, have not gained wider acceptance, and some researchers even suggest the use of indexes to represent the disputed series of plosives. On the other end of the spectrum,  suggests that Proto-Indo-European reconstructions are just "a set of reconstructed formulae" and "not representative of any reality". In the same vein, Julius Pokorny in his study on Indo-European, claims that the linguistic term IE parent language is merely an abstraction, which does not exist in reality and should be understood as consisting of dialects possibly dating back to the paleolithic era in which those dialects formed the linguistic structure of the IE language group. In his view, Indo-European is solely a system of isoglosses which bound together dialects which were operationalized by various tribes, from which the historically attested Indo-European languages emerged.
  Proto-languages evidently remain unattested. As  puts it:
  "The first fallacy is that the comparative method is 'scientific' and can offer predictions."
  [...]
  "Another fallacy is very subtle: it is the tacit assumption that the reconstructed forms are actual and experts in this imaginary field discuss and argue among themselves as if they are realities."