Editing Comparative linguistics (section)

==Methods==
The fundamental technique of comparative linguistics is to compare [[Phonology|phonological]] systems, [[Morphology (linguistics)|morphological]] systems, [[syntax]] and the lexicon of two or more languages using techniques such as the [[comparative method]]. In principle, every difference between two related languages should be explicable to a high degree of plausibility; systematic changes, for example in phonological or morphological systems are expected to be highly regular (consistent). In practice, the comparison may be more restricted, e.g. just to the lexicon. In some methods it may be possible to reconstruct an earlier [[proto-language]]. Although the proto-languages reconstructed by the comparative method are hypothetical, a reconstruction may have predictive power. The most notable example of this is [[Ferdinand de Saussure]]'s proposal that the [[Indo-European languages|Indo-European]] [[consonant]] system contained [[Laryngeal theory|laryngeals]], a type of consonant attested in no Indo-European language known at the time. The hypothesis was vindicated with the discovery of [[Hittite language|Hittite]], which proved to have exactly the consonants Saussure had hypothesized in the environments he had predicted.

Where languages are derived from a very distant ancestor, and are thus more distantly related, the comparative method becomes less practicable.<ref>{{cite journal |last=Ringe |first=D. A. |date=1995 |title='Nostratic' and the factor of chance |journal=Diachronica |volume=12 |issue=1 |pages=55–74 |doi=10.1075/dia.12.1.04rin }}</ref> In particular, attempting to relate two reconstructed proto-languages by the comparative method has not generally produced results that have met with wide acceptance.{{Citation needed|date=April 2011}} The method has also not been very good at unambiguously identifying sub-families; thus, different scholars{{Who|date=April 2011}} have produced conflicting results, for example in Indo-European.{{Citation needed|date=April 2011}} A number of methods based on statistical analysis of vocabulary have been developed to try and overcome this limitation, such as [[lexicostatistics]] and [[mass comparison]]. The former uses lexical [[cognates]] like the comparative method, while the latter uses only [[lexical similarity]]. The theoretical basis of such methods is that vocabulary items can be matched without a detailed language reconstruction and that comparing enough vocabulary items will negate individual inaccuracies; thus, they can be used to determine relatedness but not to determine the proto-language.