Historical linguistics is a field that, perhaps more than other branches of linguistics, can be said to exhibit a certain conservatism. To be clear, this term is not meant in any traditional political sense. Rather it is meant to capture the notion that, as a discipline, diachronic studies seem to accept and build on previous theories and empirical findings to a greater extent than do most synchronic subdisciplines. This may be because data are comparatively rare and hard to come by. One result of this scarcity is that, once analyzed, there are fewer opportunities for reanalysis predicated on new data. There are, of course, occasions when more or less radical proposals are brought forward subsequently, which result in debates of the kind which are much more common in synchronic syntax, say, or phonology. The reconstruction of the Indo-European consonant system (Beekes 1995: 132–4 provides a summary), for example, continues to be debated almost two hundred years after it was first proposed.