Is historical linguistics still producing new results?

Question

My impression is that language families were established in the early XX century and, since then, there have been speculations how language families may be related but no new results, which are conclusive.

Does this mean historical linguistics has reached its limits and there is just nothing further we can do with the available data?

It is reasonable to assume that known proto languages had close relatives at the time they were spoken but they have disappeared since. Does this mean that we will never have data for further reconstructions? What can we learn from the present lack of such related languages (e.g. If PIE has no present-living close relatives, does this mean that the PIE culture dominated its historical region and other people were assimilated?)

Will we ever be able to further advance our knowledge about languages of the past? Are there any alternative methods we can use to do that (e.g. genetics)?

Answer 1

I am reminded of the famous story about how the young Max Planck was told by his professor to steer well clear of a career in physics, as there was nothing new to be discovered in that field.

In historical linguistics, or specifically Indo-European studies, since the 1990s a whole new corpus of texts in a hitherto virtually unknown language were discovered, namely Bactrian. These have revolutionised our knowledge of ancient Iranian and Indo-European languages.

Just to add: none of this has filtered down to the holy of holies of internet wisdom (“Wikipedia”).

Answer 2

There are very many things remaining to do in historical linguistics. If you set aside certain language families which have been "mostly figured out", there are still very many areas in the world where our knowledge of language relations and especially reconstruction is, shall we say, less than ideal, especially in the New World. Plus, even in a family that is pretty well worked out like Bantu, there are unresolved details – for example, what, if any, system of vowel harmony did it have; aside from knowing what the tonal phonemes were and what roots had what tones, we don't really know what the proto-language did with those tones.

There are also broader questions that are not just about reconstruction. For example, there are various sensible ideas about how sound changes like Grimm's Law come about, but the theory of sound change is pretty coarse-grained. Being able to substantiate and generalize these ideas will take quite a long time and will require an unprecedented level of observation. An example where the horse may be out of the barn is the development of the modal + "of" construction, from modal + "have". The change is far enough along that there are now people for whom the construction is "should of gone", which we can post-hoc rationalize as phonological reduction of "should have". Did this happen simultaneously at hundreds of locations? Did it get started once and spread? How does this relate to the "shoulda" alternative (is "should of" based on "shoulda", or vice versa, or are these independent changes)?

Bacteria-model language splitting is the dominant theory of language relations, but of course nobody has ever denied the relevance of language contact, and I think that as contact-induced language changes are studies in greater detail, fundamental concepts of language relatedness are bound to change, at least in some cases (in particular, when there is significant contact, as in West Africa, but not so much in Oceanic).

Answer 3

One of the most significant recent discoveries in historical linguistics is the first link between Eurasian and American language families: the Dené–Yeniseian languages.

A link between the Na-Dené and the Yeniseian families was first proposed in 1923, but the first peer reviewed publication proposing the Dené–Yeniseian language family was published in 1998. Research continued by multiple people. A 369 page collection of articles was published in 2010, and in 2012 a workshop was held on the proposed family. The current leading researcher Edward Vajda showed the results of his research, and since then the proposed family has been met with wide (though not total) acceptance. The evidence includes cognate lexemes and morphology, proposed phonological changes, and genetic evidence.

Answer 4

There are whole deserts covered with bazalt stones bearing incredible numbers of Semitic inscriptions, connected to the general idea of Pre-Islamic Old Arabic waiting to be deciphered, edited and published. And then comes the fun of inferring all kinds of linguistic Semitic data from them.