An Celtlyver

"Sea" as a gender-neutral neo-pronoun

Background

While Modern Irish only has two grammatical genders, Old Irish had a third. "(H)ed" was the neuter pronoun, and was the equivalent to the English "it".

In Modern Irish, "(s)ea" survives as a pronoun used only with the copula.

Proposed usage as a gender-neutral neo-pronoun

Subject	Sea	Sé	Sí	Siad
Object	Ea	É	Í	Iad
Emphatic subject		Seisean	Sise	Siadsan
Emphatic object		Eisean	Ise	Iadsan
Possessive	A	A^S	A^H	A^U

"A" (neut.) would cause no mutations of any sort. Compare "a" (masc.) which causes a séimhiú (^S), "a" (fem.) which causes H-prothesis (^H), and "a" (plural) which causes an urú (^U):

A úll, a cat - xir apple, xir cat
A úll, a chat - his apple, his cat
A húll, a cat - her apple, her cat
A n-úll, a gcat - their apple, their cat

In Old Irish, "a" (neut.) caused a séimhiú, the same as "a" (masc.), however I think the neuter pronoun should be given different mutation rules in order to distinguish the two.

One problem that arises with creating neo-pronouns in Irish is that 15 sets of prepositional pronouns must be made as well. In Old Irish, the neuter pronoun was conjugated the same as the masculine one, however, if we want to create a truly neutral option, then I think these forms must feel distinct enough from both their masculine and feminine counterparts.

Réamhfhocal	Céad phearsa		An dara pearsa		Tríú pearsa
	Uatha	Iolra	Uatha	Iolra	Uatha			Iolra
	Mé	Muid	Tú	Sibh	Sé	Sí	Sea	Siad
Ag	Agam	Againn	Agat	Agaibh	Aige	Aici	Aga	Acu
Ar	Orm	Orainn	Ort	Oraibh	Air	Uirthi		Orthu
As	Asam	Asainn	Asat	Asaibh	As	Aisti		Astu
Chuig	Chugam	Chugainn	Chugat	Chugaibh	Chuige	Chuici	Chuga	Chucu
De	Díom	Dínn	Díot	Díbh	De	Di	Dea	Díobh
Do	Dom	Dúinn	Duit	Daoibh	Dó	Di		Dóibh
Faoi	Fúm	Fúinn	Fút	Fúibh	Faoi	Fúithi		Fúthu
Fara	Faram	Farainn	Farat	Faraibh	Fairis	Fairsti		Farstu
I	Ionam	Ionainn	Ionat	Ionaibh	Ann	Inti	Inn	Iontu
Idir	Idir mé	Eadrainn	Idir tú	Eadraibh	Idir é	Idir í	Idir ea	Eatarthu
Le	Liom	Linn	Leat	Libh	Leis	Léi	Leas	Leo
Ó	Uaim	Uainn	Uait	Uaibh	Uaidh	Uaithi		Uathu
Roimh	Romham	Romhainn	Romhat	Romhaibh	Roimhe	Roimpi		Rompu
Thar	Tharam	Tharainn	Tharat	Tharaibh	Thairis	Thairsti		Tharstu
Trí	Tríom	Trínn	Tríot	Tríbh	Tríd	Tríthi		Tríothu
Um	Umam	Umainn	Umat	Umaibh	Uime	Uimpi		Umpu