Why does furigana often appear in the most unnecessary places in Japanese books?


I'm been starting to try to read some Japanese novels recently, and one thing
that struck me was that when furigana is used, it seemed to show up in the
most unnecessary places.

For example, in the first few pages of Haruki Murakami [The Wind-Up Bird
Chronicle (ねじまき鳥クロニクル)](https://en.wikipedia.org/wiki/The_Wind-
Up_Bird_Chronicle), furigana was given for

猫 【ねこ】、椅子【いす】、眺【なが】める、泥棒【どろぼう】、恰好【かっこう】、悪戯【いたずら】、and 蜘蛛【くも】,

all of which are common words that I'd guess are easily readable by most
Japanese 10-year olds.

Maybe the last two are there since those words are usually written in kana,
but the first two for example, make no sense at all.




I think the reasons are all various. According to the Association of Japanese
Newspapers, 椅子 is “a word with complex kanji or an existing tradition of
writing in hiragana,” that should prescriptively be supported by hiragana in
writing. 猫, meanwhile, is a word that is known from childhood but its kanji is
taught relatively late. 悪戯 is a very non-Jōyō usage, not listed among the
allowed non-standard readings in the Jōyō, 蜘蛛 is literally made of non-Jōyō
kanji. The novel was published in 1994-95, so 眺める and 泥棒 can be explained by
the fact that 眺 and 泥 are still recent additions of 1981 and not everyone is
guaranteed to know them. Only 格好 remains an outlier, but perhaps it is used in
a context where rendaku is possible, to prevent がっこう? Also, apparently, in
spoken Japanese it can be reduced to かっこ, and it could be to prevent that.




I think the reasons are all various. According to the Association of Japanese
Newspapers, 椅子 is “a word with complex kanji or an existing tradition of
writing in hiragana,” that should prescriptively be supported by hiragana in
writing. 猫, meanwhile, is a word that is known from childhood but its kanji is
taught relatively late. 悪戯 is a very non-Jōyō usage, not listed among the
allowed non-standard readings in the Jōyō, 蜘蛛 is literally made of non-Jōyō
kanji. The novel was published in 1994-95, so 眺める and 泥棒 can be explained by
the fact that 眺 and 泥 are still recent additions of 1981 and not everyone is
guaranteed to know them. Only 格好 remains an outlier, but perhaps it is used in
a context where rendaku is possible, to prevent がっこう? Also, apparently, in
spoken Japanese it can be reduced to かっこ, and it could be to prevent that.

