What's the difference between 世間{せけん} and 世界{せかい}?

Question

Both 世間{せけん} and 世界{せかい} seem to mean "world" in the sense of "a sphere of human activity or interest", or "a particular way of life", and that sort of thing. (As opposed to 地球{ちきゅう}, the literal globe of a planet we live on.)

What is the difference between them, though?

Bonus question: When looking up the above words, I came across this odd variant: 浮世{うきよ}, which also means "world", but also means "this fleeting life". It conveys the temporariness of being in this world. Is it interchangeable to any degree with the above words, or is it strictly poetic and reserved for flowery ruminations?

Answer 1

In my feeling, those sound quite different.

世間 : the Japanese society.

　　ex. "世間の常識" = common sense of our society.

世界 : the whole world on the globe. Particularly outside of Japan.

　　ex. "世界のニュース" = international news. "世界一周" = a round-the-world trip.

In short, "世間" sounds like more local stuff.

is it (浮世｛うきよ｝) strictly poetic and reserved for flowery ruminations?

Yes I think so. Never used in daily life.

Answer 2

"someone" is "he" or "she" talking you.（Japanese language don't have to have subject in sentence.So I buried it temporarily.）

世間： 自分の身近にある世界。知り合いなどの直接やりとりできる人たちから感じられる世界（空気）。 A world that is familiar to someone.Atmosphere that can be felt from those who can communicate directly with someone.

世界： 日本も含まれるが「海外」というニュアンスが強い。 Japan is included, but the nuance "overseas" is strong.

例えば、「世界には悲惨な現実があります。」というように使われます。 For example, it is used like "there is a miserable reality in the world（世界）".

For your info.You can watch thesaurus.

世間の同義語 - 類語辞典(シソーラス) https://thesaurus.weblio.jp/content/%E4%B8%96%E9%96%93 大衆 ・ 俗衆 ・ 世人 ・ 世俗 ・ 民衆 ・ 衆人

世界の同義語 - 類語辞典(シソーラス) https://thesaurus.weblio.jp/content/%E4%B8%96%E7%95%8C 分野 ・ 国 ・ 領域 ・ 現実