発する, 罰する, 反する, etc. taking strange conjugation せられる for the passive form


I am sure this has been asked before, but due to this form's similarity to the
causative-passive (e.g. **行かせられる** ), I simply cannot find anything except for
some thick Japanese explanations complete with overly technical grammar terms.

I do not understand why the passive form is **せられる** instead of **される** for
verbs like `発する, 罰する, 反する`, and so on (so-called **する verbs**?). The
conjugation table on _Tangorin_ does not even list this **せられる** form at all.

**Question:**  
Is the form **される** , e.g. **発される** , `ungrammatical, unnatural, or allowed`?
Moreover, do these verbs have other ~~naughty naughty~~ irregular conjugations
that I have to look out for?

On a side note, I once read a discussion that said the alternative form of
this type of verb (e.g. **罰す** ) is not used anymore, but I cannot locate that
discussion. Would someone kindly shed light on this as well?

またつまらない質問を出してしまったが、どうぞよろしくお願いいたします！




Based on the "Best answer" from
<https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1118086201> *, and
summarizing dramatically to fit your questions:

## Short answer

  * せられる is one form of classical Japanese for される. It's not an incorrect conjugation, but it's not a mainstream conjugation, either. For the verbs in question, I imagine that usage of this non-mainstream conjugation has remained active until now, for one reason or another.

## Other noteworthy info

  * せさせる is one form of classical Japanese for させる
  * せぬ is one form of classical Japanese for しない. One modern use I've seen frequently is 予期せぬ

*(The post is a few years old, so at least one referential link from that post seems to be obsolete, but the following should at least get you started on further research if you wish.)




Based on the "Best answer" from
<https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1118086201> *, and
summarizing dramatically to fit your questions:

## Short answer

  * せられる is one form of classical Japanese for される. It's not an incorrect conjugation, but it's not a mainstream conjugation, either. For the verbs in question, I imagine that usage of this non-mainstream conjugation has remained active until now, for one reason or another.

## Other noteworthy info

  * せさせる is one form of classical Japanese for させる
  * せぬ is one form of classical Japanese for しない. One modern use I've seen frequently is 予期せぬ

*(The post is a few years old, so at least one referential link from that post seems to be obsolete, but the following should at least get you started on further research if you wish.)

