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synonym Comparative
遡る
VS
所以

Differences Between "遡る" and "所以"

Option A
遡る
Meaning
to go back (in time, upstream, to the source)
Reading
さかのぼる (sakanoboru)
Syllabus Level
N2
Practical Example
歴史を遡ると、この町の起源は古代にまで行き着く。
Tracing back through history, the origin of this town goes back to ancient times.
Option B
所以
Meaning
reason; cause; origin; source; the reason why...
Reading
ゆえん (yuen)
Syllabus Level
N1
Practical Example
彼が成功した所以は、たゆまぬ努力にあった。
The reason he succeeded was his tireless effort.

Which one to use?

Select the correct Japanese word for this context

Which word fits this context: "(to go back (in time, upstream, to the source))"?
🎉 正解 / Correct!
使い分け解説:
- 遡る: Often used when tracing origins, history, or going against a current (literally or figuratively). Implies moving against the normal flow.
- 所以: A formal and somewhat literary term. Often used in the pattern 「〜の所以」 or 「〜する所以」 to explain the fundamental reason, origin, or essence of something, implying 'the very reason why something is as it is'.
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