Does てこそ have a diffrent nuance compared to ので in a sentence like this?


縁の下。。。か

どんな業界も そういう人たちがいてこそ成り立つんだよね

My reading is "Behind the scenes.. no matter the business circles, because
people like that exist, they can function"

However, wouldn't the sentence work with ので all the same?




The -te form of the verb can have a variety of meanings, but to simplify,
consider it to have these basic meanings, 'and then', 'and so', 'by V-ing',
'and/but', or simply 'and'.

In your example, ignoring こそ for the moment, いて should be taken to express a
consequence, 'people like that exist, and so...'.

The -te form can be followed by various markers of focus, like, は, も, but also
various kinds of restrictives like さえ, など, ばかり etc., which modify the meaning
of the verb. Some examples,

あなたのご親切に頼ってしか生きていけない

Only by relying on your kindness can I go on living.

高校を卒業してすら・さえ［も］職がないのに中途退学の君に職などあるものか

When there are no jobs even after graduation from high-school, you who are a
drop-out, can hardly to have a job or anything.

その日までの彼は家庭を壊してまで女に打ち込むなんて考えたこともなかった

Until that day he had never once thought of anything like falling in love with
a woman to the extent of breaking up his home.

And so こそ adds the meaning of 'precisely:

自然のうつくしい環境に遊んでこそ本当のありかたなのだ

The true way things should be is precisely by enjoying yourself in
surroundings where nature is beautiful.

Your example then being, 'precisely because such people exist that businesses
are established'.

そういうひとたちがいるので conveys the same meaning as a bare いて (and don't forget that で
is the -te form of だ), i.e., consequence, but it is not equivalent to いてこそ.

