The implied meaning of 日本人

Question

I understand that 日本人 means "Japanese person/people"; however, I am confused as to the implied meanings of this term. What are things that we can assume when someone uses this term? Can it mean:

1. A person whose nationality is Japanese?
2. A person whose ethnicity is Japanese?
3. A person who is living in Japan, whether or not their nationality or ethnicity is of Japanese origin (e.g. a native Italian who is currently living in Japan)?
4. A citizen of Japan, regardless of ethnicity or nationality?

How would I express each of the above ideas in Japanese if the term 日本人 does not encompass it?

This is in reference to a recent post I made on Lang-8 about iodine in the diet of people in Japan. I wanted to talk about the diet of people of the country in general, whether or not they are of Japanese origin (including nationality and ethnicity). I wasn't sure of the best way to express that idea or the other ideas I have proposed. Here is a copy of the post:

日本の人の食事にヨウ素

過去一週間, ヨウ素と甲状腺について勉強している。 日本の人が最も大量のヨウ素を食べることを知った。海藻はヨウ素の大きいもとだから, それをたくさん 食べると仮定する。

質問は幾つかあります：

１） 毎日, いくら海藻を食べているか？
２） それは, どうやって 例によって 食べる の ですか？

As an extension of this idea, what would be the implied meaning of 日本の先生?

1. A teacher that is from Japan (i.e. a teacher whose nationality is Japanese)?
2. A teacher whose ethnicity is Japanese?
3. A teacher who is giving a course on the country of Japan?

Answer 1

The answer is somewhat blurry. The clear cut example are those born in Japan, to Japanese parents [plural], and are Japanese educated. These are clearly Japanese. The one where there is almost no wiggle room is the parents. There really is no half-Japanese in Japan. It's just half or more infamously "ハーフ". It's very much an all or nothing thing. My son, despite his Japanese being far stronger than his English, will never be Japanese.

There are a handful of special cases of Japanese born to Japanese parents (abroad) who return to Japan at a relatively young age (let's say before the teenage years start) and learn to read/write at a normal Japanese level. Assuming they absorb the culture and language they're usually categorized as "Japanese", regardless if they hold another passport. If such a person chose not to live in Japan until a later age, the definition becomes blurry. You could almost assume they get an asterisk put next to their categorization, as long as they have a Japanese passport. If they have no passport, they are Nikkei.

Anyway, back to your question: In actuality the answer will vary quite a bit. When in doubt, 日本人 will usually mean the first example above. When I read your post, I imagined Japanese people, as per the same example, and I assume any high level or native speaker would do the same. If you need to specify people who are residents of Japan, a very simple　日本に住んでいる人 which will encompass expats, and long term immigrants, where the lines blur. A final one: I've only seen it for purposes of discrimination, but there is also 日本の国籍のある人 includes naturalized citizens.

This really is a cultural question I'm a afraid, but if you want to master the language, you must master the culture.

A non-direct reference dealing with the "half" issue: https://www.indiegogo.com/projects/hafu-a-film-about-the-experiences-of-mixed-japanese-living-in-japan

A look at Nikkei: http://japansociology.com/2012/01/18/what-does-it-mean-to-be-japanese-the-cases-of-nikkeijin/

Answer 2

1. 日本の国籍の方
2. 日本人
3. 日本に住んでいる方

As for 4, I can think of no good way to encompass the idea of a citizen of Japan without falling back on nationality or ethnicity.

In everyday speech some who is not asian is not a 日本人. I once tried to explain that one of my students was a black Japanese teenage (to me he is Japanese. He was raised here, goes to school here, speaks Japanese as a first language etc), but even to a very liberal open-minded audience this just did not make sense. He faces the challenge everyday of being an outsider in his home country.