Reconstruction talk:Proto-Germanic/jabai

I'm not quite sure about this reconstruction. In Gothic, the regular outcome of -ai is -a, at least if the masculine/neuter dative singular is any indication. Gothic also has two different words, which presumably must come from two distinct words. I also wonder about the o- found in some of the descendants... surely ja- would remain in them? 20:34, 12 August 2012 (UTC)
 * The o- types are presumably due to amalgamation between *jah- + *ibai. As far as I know, this is the only ur-form shown... Leasnam (talk) 20:38, 12 August 2012 (UTC)
 * From what I can tell, it appears as though there are indeed two words: one from *i- (pronomial stem) and the other built on *ja- (pronomial stem) using the same ending -ba-. So the two words are *ibai and *jabai with basically selfsame meaning. *jah ("and") joins with *ibai to form *jabai2 ("and on that condition"), again with selfsame meaning. What a mess.... So do you believe that there was a ur-form of this word in the Ur-Sprache or no? Leasnam (talk) 21:01, 12 August 2012 (UTC)
 * I've looked around some and came across two interesting discussions. The first, in an older etymological dictionary of English, mentions the OHG noun iba, which is attested according to Koebler. The dative (originally locative) singular of that noun is ibu which is the same as the conjunction. Since the OHG noun is an ō-stem, the reconstruction points to a PG noun *ibō, dative *ibōi. This in turn matches the Gothic word, since -ai > -a but -ōi > -ai. The other discussion is, which discusses the different possible forms. The etymology of jabai coming from ja + ibai is plausible at least, but it does mean that two different PG forms should be reconstructed, one with ja- and one without. But the bewildering variety of forms found makes this very difficult to sort out. We could suppose ablaut between ebōi, abōi and ubōi, but there isn't actually a reconstructible origin for a zero-grade form *ubōi, since u normally only forms before resonant consonants (l, r, m, n). And such ablaut gives no insight at all as to the reason for three different ablaut grades for the same word. The most plausible (if hard to verify) explanation I have for the different vowels is assimilation to the following consonant and vowel due to relative lack of stress. Since both b and u are labial, having a preceding e- or i- assimilate to them by becoming rounded seems reasonable. 21:03, 12 August 2012 (UTC)
 * Okay CodeCat, Thank you. I originally had it as dative of *ibō, but wasn't aware of the -oi > Gothic -ai connection. I chose the neuter, as Icelandic has a cognate in (n),  (m) "doubt". So, we are then looking at at least 2 separate entries. Should the headwords then be *jaboi: *iboi ? Leasnam (talk) 22:23, 12 August 2012 (UTC)

Reconstruction (part 2)
The Germanic words for "if" are compounds, that is, a particle *bV- suffixed to the stems *i-, *ja and *ne/*ni. There does seem to be a semantic difference between Gothic jabai and ibai, it seems. This same particle shows up as an enclitic -ba- in Gothic þauh ga-ba-dauþniþ, "even though he dies", according to Lehmann, page 55.

The particle is mostly reconstructed on the PIE level simply as *bʰe- or *bʰo-. The same particle shows up in Ancient Greek as φή (pʰḗ), which could go back to *bʰéh₁, *bʰéh₂, or lengthened grade *bʰḗ. The same particle shows up in Slavic as *bo, and in Baltic as *ba, pointing to a Balto-Slavic *ba, PIE *bʰo.

So in Germanic, the particle must have been either *bē or *bō. The form *bē would explain the the forms in Gothic -ba, but not -bai; likewise it would explain the Old High German endings in -ba, but not -bu. All of the forms, however, could be explained by the form *bō, and a secondary locative/dative extension *bōi. I think it best to assume these two forms *bō and *bōi are what we're looking at. There might have even been some kind of syntactic or semantic differentiation between them, say *bō in enclitic use and *bōi in compound/conjunctional use, with some kind of conflational overlap later on. Anyway, I'd like to put my vote in for reconstructing this word as Proto-Germanic *jabōi. Burgundaz (talk) 04:49, 15 January 2021 (UTC)
 * The puzzle is how West Germanic has mostly forms with no final vowel. How can that be explained from *-ōi? (Or from *-ai for that matter) —Rua (mew) 10:42, 15 January 2021 (UTC)
 * It isn't specifically from *-ōi, but that they reflect a form with *-ō, which must have already been a variant in Proto-Germanic already because Gothic has those same variants in iba, niba vs ibai, nibai. I'm not exactly sure what the difference between the two endings *-ōi and *-ō would have been, but because jabai is never written *jaba, we can assume that the original ending of jabai was in *-ōi, and that the forms ibai and nibai were probably influenced by it because it was much more common. So the situation in Proto-Germanic might have been *jabōi against *ibō and *nibō. Gothic probably started shifting the latter two to *ibōi and *nibōi to match *jabōi, while North-West Germanic went the other way and changed *jabōi to *jabō. Burgundaz (talk) 23:18, 15 January 2021 (UTC)