I analysed the Indo-European evidence in some detail to highlight the fact that, although Latin aqua has cognates here and there in Indo-European, its attestation is too weak to treat the word as reconstructible all the way back to Proto-Indo-European. It’s a regional word with uncertain affinities, and surely not the PIE ‘water’ word (there are better candidates for that status). Its story contains a moral: sheer similarity, even within an uncontroversial family, doesn’t mean anything by itself. There is an inherited verb root meaning ‘drink’ which looks tantalisingly similar to aqua (and was once regarded as related to it), but which has to be separated from it, given what we know today. Our improved understanding of some of the languages of the past (such as Hittite and the rest of the Anatolian clade) has forced us to abandon quite a few superficially promising etymologies. And it’s a good thing: it shows that etymologies are in principle falsifiable. All you need is a good model within which they can be evaluated.
Of course absence of evidence is not evidence of absence. It may conceivably happen that a word present in a protolanguage survives only in one language descended from it, or in a small cluster of related languages. In such cases, outgroup comparison may still enable us to recognise the word as inherited. We only need some secure external cognates and a consistent pattern of correspondences. We can’t, however, trust conclusions drawn only from the existence of vaguely similar words scattered across several families, especially if there is no pattern they could fit into because the researchers feel free to avoid real reconstructive work. If you look at Bengtson & Ruhlen (B&R)’s data, you will find many clear examples of “reaching down” (selecting isolated lookalikes and pretending they represent the families in question).
For example, words related to aqua are claimed to be present in Afro-Asiatic, while in fact all the proposed cognates come from two periferal branches: Omotic (whose very membership in Afro-Asiatic is is uncertain) and Cushitic (whose exact location in a the AA family tree is anything but clear, but which is areally close to Omotic, so that borrowing between them is hard to rule out). The meaning of the suggested cognates is sometimes ‘water’, (but also ‘[to be] wet’, ‘drink’ or ‘drops of water’). But what about the Berber, Chadic, Egyptian and Semitic branches of Afroasiatic, where no such item occurs? What about alternative ‘water’ words which can be found in Cushitic and/or Omotic? (By the way, putative cognates of aqua occur only in North Omotic.) Afro-Asiatic is a big family, with about 300 extant members. With so many languages and “related meanings” to choose from, and with no formal controls, pseudo-cognates crop up inevitably. An Amerind Etymological Dictionary (Greenberg & Ruhlen 2007) lists no fewer than seventeen different etyma meaning ‘water’: *aqʷ’a/*uqʷ’a (of course), but also *man, *poi, *re, *si, *kʷati, *p’ak, *na, *ʔali, *pan, *tuna, *c’i, *kam ~ *kom, *to ~ *do, *kona, *xi, and *hobi (while we’re at it, there are also eight Amerind words for ‘dog’ and thirteen for ‘eye’). These forms are not real comparative reconstructions (their phonetic details are nowhere dicussed or justified) and must be treated as approximate, which of course makes comparison as easy as pie, especially if semantics is given as much leeway as phonology.
|Lost in distillation|
A “cognate” like “Proto-Central-Algonquian *akwā ‘from water’” may look impressive until one learns that the actual root, Proto-Algonquian *akw- (the *-ā came from the wrong segmentation of an Algonquian compound) means ‘ashore, out of the water’ (indicating location or direction rather than the place of origin) and that the real Algonquian ‘water’ term is *nepyi (for details, as well as the for full review of other Algonquian data cited by B&R, see Marc Picard 1998). But of course there are so many “Amerind” ‘water’ words that *nepyi could even be decomposed into more than one of them (e.g. *na + *poi).
Impressionistic comparison without any regard for methodological rigour will invariably produce the same outcome: a haphazard collection of words from, say, a dozen families and a few dozen languages (out of the world’s several thousand) which look vaguely similar and have vaguely similar meanings. How should one formulate a relationship proposal based on such evidence, so that other people could evaluate it? Surely not by listing the putative cognates and saying “look!” in the hope that the raw unanalysed evidence will speak for itself. But “global etymologists” do just that. They promise that someone, sometime, will carry out the actual comparative work, but they also claim that their data stand even without it. That’s wishful thinking, pure and simple.