を契機に
Prompted by
Use を契機に to describe a major event that acts as a 'turning point' (A) leading to a significant new state or action (B). It is highly formal and typically used in writing or news.
How It Works
The expression を契機に functions as a formal marker for a catalyst. The word 契機（けいき） literally means 'opportunity' or 'moment,' but in this grammatical context, it specifically refers to a pivotal turning point.
Key Characteristics:
- Formal Register: It is primarily used in 書き言葉（かきことば - written language）, such as news reports, academic papers, and formal speeches.
- Significant Change: It is not used for trivial daily occurrences. It implies that the event caused a meaningful transformation in behavior, policy, or status.
- Constructive Outcomes: While the catalyst itself can be negative (such as a disaster or financial crash), the resulting change (B) is typically a constructive or significant shift in policy, behavior, or development that follows the event.
Variations:
You may also see 〜を契機として or 〜を契機にして. These are functionally identical but even more formal.
Examples (3)
- オリンピック開催を契機に、都内のインフラ整備が一気に進んだ。
Prompted by the hosting of the Olympics, the improvement of the city's infrastructure progressed rapidly.
Word by Word: Olympic hosting (object) turning point as for, city-inside infrastructure improvement at once progressed.
The Olympics is a major event that served as the catalyst for a large-scale physical change in the city.
- 父は大きな病気をしたのを契機に、長年吸っていたタバコを止める決心をした。
Taking his serious illness as a turning point, my father resolved to quit the cigarettes he had smoked for years.
Word by Word: Father (topic) big illness did (nominalizer) turning point as for, long-years was-smoking cigarettes (object) quit decision did.
A serious illness is a significant life event. Here, it is the trigger for a major lifestyle change.
- リーマンショックを契機として、世界経済の構造は大きく変化した。
With the Lehman shock as the catalyst, the structure of the global economy underwent a major transformation.
Word by Word: Lehman Shock (object) turning point as, world economy's structure (topic) greatly changed.
This uses the variation '〜を契機として' to describe a historical economic shift triggered by a specific crisis.
Common Mistakes
Using it for trivial or minor daily triggers.
コンビニに行ったのを契機に、お菓子を買った。コンビニに行ったついでに、お菓子を買った。Going to a convenience store is not a 'pivotal turning point.' For minor coincidental actions, use 〜ついでに instead.
Confusing it with a simple sequence of events.
東京へ行ったのを契機に、友達に会った。東京へ行った時に、友達に会った。Unless the trip to Tokyo was a life-changing event that redefined the friendship, using 「を契機に（をけいきに）」 sounds unnaturally dramatic. Use 時（とき） for simple timing.
How It Connects
Learn This First
To understand 'を契機に', you need to be comfortable with the basic particles 'を' and 'に' which form its structure. Conceptually, it functions identically to 'をきっかけに', but it is used in more formal or academic contexts to describe a significant turning point or a historical trigger forking path.
Related Patterns
- 〜を皮切りにStarting with
Means 'starting with.' While を契機に marks a change in state, 〜を皮切りに marks the first in a series of similar actions.
Level 4 - 〜ついでにWhile at It
Used for minor, secondary actions done while doing something else, whereas を契機に is for major shifts.
Level 3 - 〜際にOn the Occasion of
A formal way to say 'when' or 'on the occasion of,' but it lacks the 'turning point' nuance of を契機に.
Level 3 - によってBy/depending on
A general marker for cause or means, whereas を契機に specifically highlights the event as a catalyst for change.
Level 3
Words in This Pattern
Practice を契機に in Bubblegum
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