〜によって

The Japanese particle compound 〜によって (ni yotte) is one of the most versatile and essential structures for intermediate to advanced learners. At its core, it functions as a multi-purpose connector that links a noun to a result, a method, an agent, or a variation. While English speakers might translate it differently depending on the context—using words like 'by,' 'due to,' 'through,' or 'depending on'—in Japanese, these concepts are unified by the underlying logic of 'reliance' or 'originating from.' The phrase is derived from the verb yoru (依る/寄る), which means to lean on, to depend on, or to approach. When you use 〜によって, you are essentially saying that the following action or state exists because of, or in relation to, the preceding noun.

1. The Passive Agent

In passive sentences, especially those involving creation, discovery, or invention, 〜によって identifies the person or entity that performed the action. This is more formal than the standard 'ni' particle used in basic passive sentences. For example, 'This book was written by Soseki' uses this form to give a sense of objective reporting or historical fact.

2. Cause and Reason

When describing a situation that resulted from a specific event or circumstance, 〜によって functions like 'due to' or 'because of.' It is frequently seen in news reports regarding natural disasters, accidents, or social changes. It implies a direct causal link between the noun and the outcome.

3. Means and Method

This usage translates to 'by means of' or 'through.' It describes the tool, technique, or process used to achieve a goal. However, it is generally reserved for significant methods or systems rather than everyday tools like pens or chopsticks (which use the particle 'de').

4. Variation and Diversity

When followed by words like 'chigau' (to differ) or 'iroiro da' (is various), it means 'depending on.' It sets the criteria for variation, such as 'depending on the country' or 'depending on the weather.'

Understanding the context is key to mastering this particle. When you see it, look at the end of the sentence. If the sentence ends with a passive verb, it's likely the agent. If it ends with a result, it's the cause. If it ends with a word for 'different' or 'various,' it's the criteria for variation. This logical flow makes Japanese sentences highly structured and predictable once you recognize the pattern. In academic writing, this particle is indispensable for citing sources and explaining experimental methods, making it a gateway to higher-level Japanese proficiency.

Mastering the syntax of 〜によって requires understanding its grammatical placement and its variations. It is always preceded by a noun or a noun phrase. Unlike some particles that can follow verbs directly, 〜によって requires a nominalized form if you want to link it to an action. The grammatical structure is consistent, but the meaning shifts based on the surrounding sentence elements. Let's break down the primary grammatical patterns and how they function in real-world Japanese.

Pattern A: Noun + によって + Verb (Adverbial Use)

This is the most common form. Here, the phrase acts as an adverbial modifier for the verb that follows. It explains 'how' or 'why' the action happened. For example: 'By studying hard (method), I passed.' or 'Due to the rain (cause), the game was cancelled.' The 'te' at the end of 'yotte' signals a connection to the following clause.

Pattern B: Noun + による + Noun (Adjectival Use)

When you want to describe a noun using the relationship of cause, method, or agent, you use 'ni yoru.' This functions like an adjective. Example: 'A decision by the committee' (Iinkai ni yoru kettei). This is very common in formal titles, news headlines, and technical documents where conciseness is valued.

Pattern C: Noun + によっては (Focus/Limitation)

Adding the topic marker 'wa' to 'yotte' creates 'ni yotte wa.' This emphasizes a specific case among many possibilities. It often translates to 'In some cases, depending on...' For example: 'Depending on the person (ni yotte wa), some might disagree.' It narrows the scope to specific instances within a category.

When using it to mean 'depending on,' the sentence usually concludes with verbs like kotonaru (to differ), wakareiru (to be divided), or adjectives like samazama (various). This structure is vital for expressing relativity in Japanese culture, where absolute statements are often avoided in favor of nuanced, context-dependent observations. For instance, 'The way of thinking differs by generation' (Sedai ni yotte kangaekata ga kotonaru) is a quintessential Japanese observation that relies on this grammar.

Finally, in the 'means/method' sense, ensure the method is a system or a significant action. You wouldn't say 'I went by bus' using 'ni yotte' in daily life; 'basu de' is correct. However, if you were writing a report on urban planning, you might say 'The city was developed by means of a new bus system' (Atarashii basu shisutemu ni yotte...), as this describes a large-scale method or systemic change. This distinction between 'de' (everyday tool) and 'ni yotte' (significant method) is a hallmark of N3/N2 level Japanese.

You will encounter 〜によって in environments where precision, formality, and objective reporting are required. While it is less common in a casual izakaya conversation among friends, it is the 'bread and butter' of professional and academic Japanese. If you turn on the NHK news, read a Japanese newspaper like the Asahi Shimbun, or attend a university lecture, you will hear it constantly. Understanding its context helps you switch between 'casual learner' and 'proficient communicator.'

1. News and Media Reports

Journalists use 〜によって to report causes of events without sounding biased. 'Due to heavy snow, the trains stopped' (Ooyuki ni yotte densha ga tomatta). It provides a clear, factual link. You'll also hear it when a reporter says 'According to our investigation...' (Chousa ni yotte...), though 'ni yoreba' is a more specific alternative for 'according to.'

2. Academic and Scientific Contexts

In research papers, this particle is used to describe methodology. 'The experiment was conducted by means of a new algorithm' (Atarashii arugorizumu ni yotte...). It is also used to attribute theories or discoveries to specific scientists, maintaining a formal and respectful tone.

3. Business and Corporate Settings

During meetings, you'll hear it when discussing strategies or outcomes. 'By improving the workflow, we increased efficiency' (Waakufuroo no kaizen ni yotte...). It is also used in contracts and terms of service to define conditions: 'Depending on the situation, the service may be suspended' (Joukyou ni yotte wa...).

In documentaries or museum exhibits, you will frequently see 〜によって used to describe the creation of art or the founding of institutions. 'This temple was built by the Emperor' (Kono tera wa tenno ni yotte taterareta). This usage elevates the subject, giving it a sense of historical weight. For learners, recognizing this particle is a signal that the information being presented is factual, formal, and structured. It helps you mentally categorize the incoming Japanese as 'official' or 'informative' rather than 'interpersonal' or 'casual.'

While 〜によって is a powerful tool, it is often misused by learners who apply it too broadly or confuse it with simpler particles. Because it translates to 'by' or 'with' in many cases, the temptation to use it in place of the particle 'de' (で) is high. However, Japanese is very specific about the 'scale' and 'formality' of the method or cause being described. Let's look at the most frequent errors and how to avoid them.

Mistake 1: Using it for Everyday Tools

Incorrect: 'Pen ni yotte tegami o kaku' (I write a letter by means of a pen).
Correct: 'Pen de tegami o kaku.'
Explanation: 〜によって is for significant methods, systems, or processes. For physical tools or simple means of transport, always use 'de.' Using 'ni yotte' for a pen makes it sound like the pen is a revolutionary technology or a complex system.

Mistake 2: Confusing with 'Ni Yoreba' (According to)

Incorrect: 'Kare ni yotte, ashita wa ame da sou da' (By him, I heard it will rain tomorrow).
Correct: 'Kare ni yoreba...'
Explanation: If you are citing a source of information, use 'ni yoreba.' 'Ni yotte' would imply that he is the *cause* of the rain or the *agent* who created the rain, which is likely not what you mean!

Mistake 3: Using it for Personal Reasons in Casual Speech

Incorrect: 'Byouki ni yotte yasumimasu' (I will be absent due to illness - said to a friend).
Correct: 'Byouki nanode yasumimasu.'
Explanation: 〜によって is very formal. Using it for personal, everyday reasons in a casual setting sounds stiff and unnatural. It’s better suited for a formal email to a professor or a public announcement.

Another common pitfall is failing to change 'ni yotte' to 'ni yoru' when modifying a noun. For example, 'Damage by the fire' should be 'Kaji ni yoru higai.' If you say 'Kaji ni yotte higai,' the sentence feels unfinished because 'ni yotte' is an adverbial form looking for a verb to modify. Always check if the following word is a noun or a verb to decide between 'yotte' and 'yoru.'

Japanese has several ways to express cause, method, and dependency. Choosing the right one depends on the level of formality and the specific nuance you want to convey. 〜によって is the 'formal all-rounder,' but these alternatives are often more appropriate in specific situations.

1. 〜で (De) vs. 〜によって

'De' is the everyday version of 'ni yotte' for both cause and method.
Example: 'Kaze de yasumu' (Absent due to a cold) vs. 'Byouki ni yotte kesseki suru' (Absent due to illness - formal). Use 'de' for physical tools, transport, and casual reasons. Use 'ni yotte' for systems, large-scale causes, and formal reports.

2. 〜により (Ni yori) vs. 〜によって

'Ni yori' is even more formal than 'ni yotte.' It is the 'masu-stem' form of the verb 'yoru.' You will see this in very formal writing, speeches, or official notices. It functions identically to 'ni yotte' but adds an extra layer of literary polish.

3. 〜に従って (Ni shitagatte) vs. 〜によって

While 'ni yotte' means 'depending on' (variation), 'ni shitagatte' means 'in accordance with' or 'as something changes.'
Example: 'Rules differ depending on the country' (ni yotte) vs. 'As the temperature rises...' (ni shitagatte). Use 'ni yotte' for static differences and 'ni shitagatte' for proportional changes.

4. 〜を通じて / 〜を通して (Wo tsuujite / Wo tooshite)

These mean 'through' or 'via.' They are used when something happens through a medium or over a period of time.
Example: 'I met her through a friend' (Tomodachi o tooshite). 'Ni yotte' is more about the *method* that caused the result, while 'wo tooshite' is about the *channel* or *medium* used.

When deciding which to use, ask yourself: 'Is this a news report?' (Use ni yotte). 'Am I talking to a friend?' (Use de/node). 'Is this a physical tool in my hand?' (Use de). 'Am I describing a source of information?' (Use ni yoreba). By filtering your choice through these questions, you will sound much more like a native speaker and avoid the 'stiff' or 'unnatural' textbook Japanese that many intermediate learners struggle with.