Editing Openai/69186d20-2d14-8013-b9c6-c09000f173f6 (section)

=== Assistant: 2511141903ET ===
251114_1903ET

short answer: sort of, but not like Proto-Germanic or Proto-Slavic.

There is no single, widely-accepted full reconstruction of “Proto-Italo-Celtic” (with its own standard phoneme system, dictionary, full paradigms). What exists is:
* a cluster of shared innovations in Italic + Celtic, and
* local reconstructions of specific Proto-Italo-Celtic forms or morphological patterns in specific papers/grammars.

So:
* **If “reconstructed” = “people posit a common stage and write forms like *wiro-ī ‘man-GEN.SG’ or **so-isamos ‘the most X’” → yes.*
* If “reconstructed” = “there is a generally used Proto-Italo-Celtic grammar & lexicon like we have for Proto-Germanic” → no.

===== In the literature you’ll see things like: =====
'' Shared genitive singular in -ī for thematic nouns: - reconstructed ''Proto-Italo-Celtic GEN.SG -ī, continued by Latin -ī and Old Irish -i in certain patterns.
'' Superlatives in ''-isamo- / -issimo-: - Latin -issimus, Old Irish superlative formations from the same -isamo- template → people write Proto-Italo-Celtic *gʷr̥h₂-isamos “oldest”, etc.
'' ''A specific ''-ā- subjunctive/future'' pattern in the verb system, reconstructed as a shared Italo-Celtic innovation.

These are often explicitly labelled “Proto-Italo-Celtic” in academic prose for convenience, but you’re looking at individual reconstructed morphemes or paradigms, not a fully fleshed proto-language.

===== Three main reasons: =====
# Subgroup status is debated. - Some see Italic + Celtic as a true genetic subgroup (real Proto-Italo-Celtic). - Others see the similarities as very early areal convergence among already distinct Italic and Celtic branches. - If you’re in the second camp, you deliberately avoid reconstructing a full Proto-Italo-Celtic language.
# Data is patchy on the Celtic side. - We have lots of Latin, but very limited Continental Celtic (Gaulish, Celtiberian), and Old Irish is already pretty far downstream. - That makes a robust phonological reconstruction above Proto-Celtic less secure than, say, above Proto-Germanic.
# Most Italo-Celtic evidence is ''systemic'', not lexical. - It’s about endings, superlatives, subjunctive patterns, not a big pile of exclusive Italo-Celtic vocabulary. - So people naturally talk about a “layer of shared innovations” more than about a full separate proto-lexicon.

===== The “safe” picture, given your phylogenetic taste: =====
* PIE → some West-IE zone where Italic and Celtic are in tight early contact.
'' Within that zone, there’s a set of shared innovations you can legitimately reconstruct to a Proto-Italo-Celtic ''stage*.
* For individual problems (e.g. explaining the Latin/Old Irish superlative system), scholars do reconstruct Proto-Italo-Celtic forms.
* But there is no canonical, global Proto-Italo-Celtic reconstruction that everyone uses in the way they use Proto-Germanic.

So if you say:

: 

you’re capturing the actual state of the field pretty well.