Can 故の mean "because" without a が preceding it?

Question

I came across this line while reading a manga but was stuck on the 故の portion.

知識欲が行き過ぎた故の職業病なのぉ？

I understood this sentence as, "It's an occupational disease because of (your) excessive thirst for knowledge."

However when I tried looking up for more sentences with 故の functioning as "because", they all had が's before them. Furthermore, I read that 故の is also not a term that'd be used in daily conversation, which has me puzzled since this conversation is between two friends in a cafe.

Could it be that the が was simply just dropped because of the casual nature of the conversation? Or does 故の mean something else in this context?

Answer 1

This 故【ゆえ】 is a special type of noun called 形式名詞 ("formal noun" in the sense of "technically/apparently a noun"). Other formal nouns include とき, ため, はず, etc.

Since 故 is a (formal) noun, something that modifies it must be an attributive (i.e., "noun-modifying") expression. So what are "noun-modifying" in Japanese?

• Attributive form of an adjective

  あまりに小さい故にむしろ不便だ。
  自由な故の悩み

• Noun + の / No-adjective + の

  不勉強の故に分かりません。
  彼は軽い性格の故によくトラブルを起こしている。

• Attributive form of a verb, a.k.a. a relative clause

  真剣に見る故に欠点も見えてくる。
  知識欲が行き過ぎた故の職業病

• Lexicalized attributives (その, この, etc)
• Attributive form of a verb + が

  真剣に見るが故に欠点も見えてくる。
  知識欲が行き過ぎたが故の職業病
  小さ過ぎるが故に使いづらい。
  彼は軽い性格であるが故によくトラブルを起こしている。

The first four bullets should be easy if you understand 故 is technically a noun. They are all valid usages of 故に/故の.

The last one may seem tricky if you don't know what's going on. This is a special construction derived from Old Japanese. This が is actually a linking particle like の, and the verb before it is actually a nominalized verb. Please read: Why is there a が in 深淵に臨むが如し?

Since 故 is a stiff and literary expression, it still tends to be used along with が when it is modified by a verb. But other simpler usages are also perfectly possible. To put this simply, the が between the verb and 故 is optional. In your case, there is another が near 故, so I even feel the sentence sounds slightly better without が before 故.

Finally, it's not that odd to use 故の in casual conversations. Using a bit of idiomatic expressions from archaic Japanese is usually natural. See: Nuance and conversational use of なきにしもあらず

Answer 2

In my opinion, 行き過ぎた故の is not common for me, buy it seems not wrong.

As you said, I guess that ～が故に/の or Noun + 故に/の (e.g. その美しさ故に/の) is more common.
However, it is almost used as literal language and We rarely use it in daily conversation.

Indeed, we occasionally use it in verbal communication.
Occasionally, you want to use a literal language or difficult word, don't you?
That is about it. That is the situation in the Manga though it is grammarly wrong...