Kanji - placement and frequency
 

I'm just a little curious about this.
My question is simple enough: "when" and "where" do you use kanji?

I see texts where something like 80% or more appears to be kanji. I turn around, and I see texts where kanji constitute something more like 10% if that much. Are there any "rules" or norms for when you use kanji and when you use kana?

I could be wrong but I'd assume the ammount of kanji used would perhaps depend on the reading age of the text. Children begin learning only kana, then gradually work up learning more kanji. So if the text was 80% kanji perhaps it's due to it being aimed at a more adult readership?

Well, that's a possibility, but I was wondering about more general rules if the text doesn't target a specific target age?

There are words that have kanji that are typically not written in kanji by careful writers of Japanese. Sashimister has made this point. NagoYankee made a similar point a year or two ago. allhailhata has made the opposite point before, claiming this is a recent trend. They are all three native speakers.

For example, I was corrected by my Japanese professors when I'd write だいたい in kanji （大体） or ありがとう（有り難う） and such. Similarly, do not write 出来る in kanji, but do write 出来事 in kanji!

Sometimes you even get political correctness debates within the Japanese community: some claim writing こども as 子供 is bad, as it implies the child "belongs" to the adult (as in property), and so it should be written 子ども or こども instead. Similar claims have been made about 主人 (husband, literally "master") and 家内 (wife, literally "inside the house"). But those two are more arguments about the words rather than whether to use kanji or not, IIRC.

You just learn as you go based on when you've seen the kanji used in good writing like newspaper articles, books, etc.

I can see how the "master"/"inside the house" wouldn't be particularly popular. (Especially with feminists. :D)

Anyways, thanks for a long and enlightening answer.

And yet the "master" way of saying it is still totally normal and used all the time mainly by women, while the "inside the house" seems to be falling out of favor and only used by the older generation. (It is really only a phrase used by men.)

As for the distribution of kanji - really, it does come down to subject content and to a lesser extent the writer`s style. The more complex a passage is, the more likely it is to have lots of kanji. Both 80% and 10% seem like far extremes. Most passages are going to be somewhere between that.

Also, I think you have to keep in mind that one kanji is not one word. In more difficult texts you will find tons of multi-kanji words. 4 and 5 kanji words abound... So you can end up with countless kanji but not all that many words.