によって

The Japanese particle construction によって (ni yotte) is one of the most versatile and essential tools in the Japanese language, particularly as a learner moves into the intermediate (B1) and advanced (B2-C1) stages. At its core, it functions as a compound particle that connects a noun to a verb or adjective to express a relationship of cause, means, agency, or variation. It is derived from the verb yoru (依る/拠る/因る), which means 'to depend on' or 'to be based on.' In everyday conversation, you might hear it used to explain why something happened or how something was accomplished, but its true home is in formal writing, news broadcasts, and academic discourse.

The Four Pillars of Usage

1. Cause and Reason: Expressing that 'A' happened because of 'B'. 2. Means and Method: Explaining that 'A' was achieved through the method of 'B'. 3. Passive Agency: Identifying the creator or doer in a passive sentence (e.g., 'written by'). 4. Diversity and Variation: Expressing that something changes 'depending on' the circumstances.

When people use ni yotte, they are often elevating the register of their speech. While a beginner might use the simple particle で (de) to say they go to school by bus, an intermediate speaker might use ni yotte to describe how a new scientific discovery was made through rigorous testing. This distinction is crucial; ni yotte implies a more formal, logical, or systematic connection than the multipurpose de. It suggests a direct correlation or a definitive method that is worth noting specifically.

In the context of diversity, ni yotte is the gold standard for expressing subjectivity or relative truths. Phrases like 'It depends on the person' (hito ni yotte) or 'It varies by country' (kuni ni yotte) are foundational for nuanced communication. It allows the speaker to avoid overgeneralization, showing a sophisticated understanding of the world's complexities. This usage is perhaps the most common in daily life, appearing in discussions about tastes, habits, and cultural differences.

Register and Tone

This grammar point is markedly more formal than de or node. In casual speech, Japanese speakers often shorten it to ni yotte sa... or avoid it entirely in favor of more colloquial structures. However, in business meetings or essays, failing to use ni yotte can make your Japanese sound overly simplistic or childish.

Finally, it is worth noting the grammatical flexibility of this particle. It can take several forms depending on the word that follows it: ni yotte (adverbial), ni yoru (adjectival, modifying a noun), and ni yoreba (according to). Understanding these variations is key to mastering the B1 level and beyond. Each variation maintains the core concept of 'dependence' or 'origination' but fits into different syntactic slots in the sentence, allowing for complex and descriptive Japanese prose.

Mastering the syntax of によって requires understanding how it attaches to nouns and how its form changes based on its role in the sentence. The most basic pattern is [Noun] + によって. This acts as an adverbial phrase, modifying the verb that follows. For example, in the sentence 'I learned through the internet,' the 'internet' is the noun, and 'by means of' is the particle.

Pattern 1: Cause and Effect

Used to indicate the source of a result, often a negative one like a disaster or an error.
Example: 大雨によって、電車が止まりました (Due to heavy rain, the trains stopped).

When you want to use the cause to modify a noun directly, you must change the form to による. This is the attributive form. For instance, 'Damage caused by the earthquake' becomes jishin ni yoru higai. This distinction is a frequent source of errors for learners. Remember: ni yotte points to an action (verb), while ni yoru points to a thing (noun).

Pattern 2: Means and Method

This indicates the tool or method used. It is more formal than de.
Example: 話し合いによって解決しましょう (Let's resolve it through discussion).

The third major use is the passive agent. In English, we say 'This book was written by Orwell.' In Japanese, for historical facts, artistic creations, or scientific discoveries, ni yotte is the standard agent marker in passive sentences. Using the simple ni (the standard passive agent marker) in these specific contexts can sometimes sound slightly off or too personal. Ni yotte provides the necessary objective distance for formal reports.

Pattern 3: Variation

[Noun] + によって + [Verb of change/difference].
Example: 季節によって景色が変わります (The scenery changes depending on the season).

Finally, note the existence of によっては. Adding the topic marker wa narrows the focus to a specific case among many. While ni yotte generally means 'depending on,' ni yotte wa specifically means 'in some cases' or 'depending on the specific X.' For example, 'Depending on the person, they might not like it' (hito ni yotte wa...) suggests that while some people are fine, there are specific individuals who are not.

If you turn on the NHK evening news, you will hear によって within the first five minutes. It is the language of reporting. News anchors use it to describe the causes of traffic accidents, the methods of new government policies, or the effects of international events. For example, 'Due to the decline in the birthrate...' (shoushika ni yotte...) is a common opening for social analysis segments. It lends an air of objectivity and factual reporting that more casual particles lack.

In the Academic World

University lectures and research papers are saturated with ni yotte. It is used to define methodologies ('By analyzing the data...') and to attribute theories to specific scholars ('According to the theory proposed by...'). If you are planning to study at a Japanese university, this particle is non-negotiable.

In the business environment, ni yotte appears in contracts and official emails. It is used to specify terms: 'Depending on the contract type, the fee varies.' It is also used in troubleshooting: 'The error was caused by a system glitch.' Using this particle in a professional setting shows that you can communicate logical relationships clearly and respectfully. It moves the conversation from 'I think this happened' to 'The evidence shows this happened because of X.'

Interestingly, you also hear it in museums and historical sites. Plaques describing artifacts will almost always use ni yotte to identify the creator or the era's influence. 'This statue was carved by...' or 'This style was influenced by...' are standard constructions. It acts as a bridge to the past, providing a formal attribution that respects the historical significance of the subject matter.

In daily conversation among friends, you will hear the 'depending on' usage most frequently. Friends might discuss travel plans and say, 'It depends on the weather' (tenki ni yotte ne). It is less common to use the 'cause' or 'means' versions in casual chat, as they can sound a bit stiff. Instead, friends might use de or dakara. However, even in casual settings, using ni yotte to express diversity shows a level of thoughtfulness and linguistic maturity.

One of the most frequent mistakes English speakers make is confusing によって (ni yotte) with the simple particle で (de). While both can mean 'by' or 'with,' de is used for everyday tools and locations, whereas ni yotte is for formal means and methods. You wouldn't say 'I ate with a spoon' using ni yotte—that would sound like the spoon was a sophisticated scientific instrument or a formal methodology.

Mistake 1: Over-formality in Daily Life

Using ni yotte for simple actions like 'I went by car' (kuruma ni yotte ikimashita) sounds very strange. Stick to kuruma de. Use ni yotte for abstract methods or formal systems like 'communication through the internet.'

Another common error is the confusion between によって (ni yotte) and によると (ni yoru to). While they look similar, ni yoru to is strictly for citing sources of information (e.g., 'According to the news...'). If you use ni yotte when you mean 'according to,' you might accidentally imply that the news caused something to happen rather than just reporting it.

The distinction between ni yotte and ni yoru (attributive form) is also a major hurdle. Remember that ni yoru must be followed by a noun. For example, 'The destruction caused by the fire' is kaji ni yoru hakai. If you say kaji ni yotte hakai, the sentence is grammatically incomplete because ni yotte expects a verb or a full clause to follow it.

Mistake 2: Misusing the Passive Agent

❌ 母によって叱られた (I was scolded by my mother - sounds too formal/epic).
✅ 母に叱られた (Standard passive for personal interactions).

Finally, learners often forget the nuance of ni yotte wa. If you say hito ni yotte chigau, you mean 'It varies by person.' If you say hito ni yotte wa, kore ga kirai da, you mean 'Depending on the person (specifically some people), they might hate this.' The wa adds a layer of 'in certain cases' that is vital for accurate expression.

Understanding によって also involves knowing when not to use it and what alternatives exist. The most direct competitor is で (de). While de is the 'Swiss Army knife' of particles, ni yotte is the 'scalpel.' Use de for physical tools (hammer, car, pen) and ni yotte for abstract methods (technology, law, effort).

Comparison: Ni yotte vs. De

De: Casual, physical tools, everyday causes.
Ni yotte: Formal, abstract methods, systematic causes.

Another similar expression is を通じて (wo tsuujite) or を通して (wo tooshite). These mean 'through' or 'via.' While ni yotte implies a direct method that causes a result, wo tsuujite implies a medium or a duration. For example, 'I met her through a friend' usually uses wo tsuujite because the friend is the medium of the connection, not necessarily the formal 'method' of meeting.

Comparison: Ni yotte vs. Ni yoru to

Ni yotte: Shows cause/method (The storm caused the delay).
Ni yoru to: Shows source of info (According to the news, there's a storm).

For the 'depending on' meaning, you might also encounter 次第で (shidai de). While ni yotte is used for general variation (It varies by country), shidai de is often used when the outcome is entirely dependent on a single factor, often in a 'make or break' sense. 'It all depends on your effort' would be doryoku shidai da, emphasizing that the effort is the deciding factor.

Lastly, consider から (kara) for cause. Kara is subjective and personal ('Because I was tired...'). Ni yotte is objective and external ('Due to the fatigue caused by long hours...'). Switching between these allows you to control the emotional distance and formality of your Japanese, a hallmark of an advanced speaker.