Where does the -a stem come from with auxiliary-constructed transitive/intransitive verb pairs if the base verb is a 二段活用 (or カ行変格活用)?


It seems to be generally understood that transitive/intransitive verb pairs,
when they are not a 四段活用 and a 二段活用 that share the same 終止形, were created by
taking a base verb, whether transitive or intransitive, and adding an Old
Japanese auxiliary - す for transitivity, and る or ゆ for intransitivity - to
the 未然形 to form the verb of opposite transitivity. For example, [減]{へ}る
(intransitive) + す = [減]{へ}らす (transitive).

But something confuses me - since auxiliaries like す、る、ゆ、ふ、etc. only attach to
the 未然形, what is the deal with 二段活用 verbs? For example, [覚]{さ}む is a 下二段活用
intransitive verb, and [覚]{さ}ます is its transitive variant.

Where does this -a stem in [覚]{さ}ます come from? The 未然形 of [覚]{さ}む is [覚]{さ}め,
not [覚]{さ}ま like if it were a 四段活用. Would it not logically be [覚]{さ}めす
instead? [上]{あ}ぐ becomes [上]{あ}がる, [満]{み}つ becomes [満]{み}たす - all of these are
二段活用 verbs, which do not feature an -a stem in their 未然形, yet the opposite
transitivity uses an -a stem. What is the reason for this?

This also seems to appear for カ行変格活用 verbs as well, as [出]{で}[来]{き}る ->
[出]{で}[来]{か}す instead of でこす.

According to the Wiktionary etymology of あぢさはふ:

> The initial adi is likely from the 䳑鴨 (ajigamo, “Baikal teal”),[1] while the
> derivation of sapapu is unknown.
>
> One theory states from 障ふ (sapu), basis for modern 障える (saeru, “to hinder,
> interrupt”, transtitive) and 障わる (sawaru, “to disturb, harm”, intransitive).
> This is problematic as sapu is a 下二段活用 (shimo nidan katsuyō, “lower bigrade
> conjugation”) verb and not a 四段活用 (yodan katsuyō, “quadrigrade conjugation”)
> verb required for a 未然形 (mizenkei, “irrealis form”) ending in -a.

This seems to suggest that 二段活用 verbs cannot simply swap to an -a stem when an
auxiliary is added (here being ふ).

There are also some verb pairs where both the intransitive and transitive
verbs have auxiliaries on a non-verbal-未然形 root, like [外]{はづ}す and [外]{はづ}る,
and there are also some curiosities like [消]{け}す and [消]{き}ゆ where the roots
are not the same vowel. What is the reason for this as well?




My major is not linguistics but I found some interesting references for you.

Aoki[1] introduces a few types of classification of transitive/intransitive
verbs in Japanese.

The first classification is written by Kuginuki[2]. It says there are 3
patterns of transitive/intransitive verb pairs.

  1. Depending on the type of conjugation (第Ⅰ群形式)

> 知る (四段活用 is an intransitive verb and 下二段活用 is a transitive verb)  
>  切る (下二段活用 is an intransitive verb and 四段活用 is a transitive verb)

  2. Depending on the termination of a word (第Ⅱ群形式)

> 成る (intransitive), 成す (transitive)  
>  寄る (intransitive), 寄す (transitive)

  3. Depending on the additional stem and additional termination of a word (第Ⅲ群形式)

> 明く (intransitive), 明かす (transitive)  
>  上ぐ (transitive), 上がる (intransitive)

The second classification is written by Okutsu[3].

  1. Transitivization (from intransitive to transitive)

> 乾く → 乾かす  
>  落ちる → 落とす

  2. Intransitivization (from transitive to intransitive)

> まげる → まがる  
>  はさむ → はさまる

  3. Polarization (from some common element to transitive or intransitive verb)

> 帰る → 帰す  
>  アク → アケル

Kageyama[4] follows the second classification. And in [4], transitivization is
classified into two patterns:

  1. intransitive verb + -e- → transitive verb

> 割る (waru) → 割れる (wareru)  
>  抜く (nuku) → 抜ける (nukeru)

  2. intransitive verb + -ar- → transitive verb

> 植える (ueru) → 植わる (uwaru)  
>  集める (atsumeru) → 集まる (atsumaru)

and also intransitivization is classified into two:

  1. transitive verb + -e- → intransitive verb

> 建つ (tatsu) → 建てる (tateru)  
>  進む (susumu) → 進める (susumeru)

  2. transitive verb + -as- or -os- → intransitive verb

> 鳴る (naru) → 鳴らす (narasu)  
>  枯れる (kareru) → 枯らす (karasu)  
>  起きる (okiru) → 起こす (okosu)

Aoki[1] summarizes the above as follows:

In 第Ⅰ群形式, 下二段活用 verb is derived from 四段活用動詞. And 第Ⅲ群形式 is derived from 第Ⅱ群形式.

And Aoki also says that auxiliaries る and す are derived from these suffixes.

So I personally think the matter of transitive/intransitive verbs has some
relationship with auxiliaries but it seems a bit different from the way you
think.

[1] AOKI Hiroshi, "On the relationship of paired yodan-shimonidan conjugation"
in 京都府立大学学術報告(人文・社会), vol.53, Dec 2001,
Available:[https://kpu.repo.nii.ac.jp/?action=pages_view_main&active_action=repository_view_main_item_detail&item_id=4083&item_no=1&page_id=13&block_id=17](https://kpu.repo.nii.ac.jp/?action=pages_view_main&active_action=repository_view_main_item_detail&item_id=4083&item_no=1&page_id=13&block_id=17)
[Accessed Jul. 13, 2021]

[2] KUGINUKI Tooru, "古代日本語の形態変化", 1996, 和泉書院,
Available:<https://nagoya.repo.nii.ac.jp/records/14721> [Accessed Jul. 13,
2021]

[3] OKUTSU Keiichirō, "自動化・他動化および両極化転形ー自・他動詞の対応" in 『国語学』第70集, Sep. 30, 1967,
Available:<https://bibdb.ninjal.ac.jp/SJL/view.php?h_id=0700460660> [Accessed
Jul. 13, 2021]

[4] KAGEYAMA Tarō, "動詞意味論－言語と認知の接点―",1996, くろしお出版, No PDF (I borrowed this
book from a library)




My major is not linguistics but I found some interesting references for you.

Aoki[1] introduces a few types of classification of transitive/intransitive
verbs in Japanese.

The first classification is written by Kuginuki[2]. It says there are 3
patterns of transitive/intransitive verb pairs.

  1. Depending on the type of conjugation (第Ⅰ群形式)

> 知る (四段活用 is an intransitive verb and 下二段活用 is a transitive verb)  
>  切る (下二段活用 is an intransitive verb and 四段活用 is a transitive verb)

  2. Depending on the termination of a word (第Ⅱ群形式)

> 成る (intransitive), 成す (transitive)  
>  寄る (intransitive), 寄す (transitive)

  3. Depending on the additional stem and additional termination of a word (第Ⅲ群形式)

> 明く (intransitive), 明かす (transitive)  
>  上ぐ (transitive), 上がる (intransitive)

The second classification is written by Okutsu[3].

  1. Transitivization (from intransitive to transitive)

> 乾く → 乾かす  
>  落ちる → 落とす

  2. Intransitivization (from transitive to intransitive)

> まげる → まがる  
>  はさむ → はさまる

  3. Polarization (from some common element to transitive or intransitive verb)

> 帰る → 帰す  
>  アク → アケル

Kageyama[4] follows the second classification. And in [4], transitivization is
classified into two patterns:

  1. intransitive verb + -e- → transitive verb

> 割る (waru) → 割れる (wareru)  
>  抜く (nuku) → 抜ける (nukeru)

  2. intransitive verb + -ar- → transitive verb

> 植える (ueru) → 植わる (uwaru)  
>  集める (atsumeru) → 集まる (atsumaru)

and also intransitivization is classified into two:

  1. transitive verb + -e- → intransitive verb

> 建つ (tatsu) → 建てる (tateru)  
>  進む (susumu) → 進める (susumeru)

  2. transitive verb + -as- or -os- → intransitive verb

> 鳴る (naru) → 鳴らす (narasu)  
>  枯れる (kareru) → 枯らす (karasu)  
>  起きる (okiru) → 起こす (okosu)

Aoki[1] summarizes the above as follows:

In 第Ⅰ群形式, 下二段活用 verb is derived from 四段活用動詞. And 第Ⅲ群形式 is derived from 第Ⅱ群形式.

And Aoki also says that auxiliaries る and す are derived from these suffixes.

So I personally think the matter of transitive/intransitive verbs has some
relationship with auxiliaries but it seems a bit different from the way you
think.

[1] AOKI Hiroshi, "On the relationship of paired yodan-shimonidan conjugation"
in 京都府立大学学術報告(人文・社会), vol.53, Dec 2001,
Available:[https://kpu.repo.nii.ac.jp/?action=pages_view_main&active_action=repository_view_main_item_detail&item_id=4083&item_no=1&page_id=13&block_id=17](https://kpu.repo.nii.ac.jp/?action=pages_view_main&active_action=repository_view_main_item_detail&item_id=4083&item_no=1&page_id=13&block_id=17)
[Accessed Jul. 13, 2021]

[2] KUGINUKI Tooru, "古代日本語の形態変化", 1996, 和泉書院,
Available:<https://nagoya.repo.nii.ac.jp/records/14721> [Accessed Jul. 13,
2021]

[3] OKUTSU Keiichirō, "自動化・他動化および両極化転形ー自・他動詞の対応" in 『国語学』第70集, Sep. 30, 1967,
Available:<https://bibdb.ninjal.ac.jp/SJL/view.php?h_id=0700460660> [Accessed
Jul. 13, 2021]

[4] KAGEYAMA Tarō, "動詞意味論－言語と認知の接点―",1996, くろしお出版, No PDF (I borrowed this
book from a library)

