Three separate systems get called politeness in Japanese and conflating them is what makes the subject feel impossible. One is how formal you are being with the person in front of you, and it lives in the verb ending. One raises the person you are talking about. One lowers you and anything belonging to you. They combine, and a sentence can be formal while raising nobody, or informal while using a humble form.
Separate the three and each becomes small. The first is a decision about a relationship, the second and third are a set of verb substitutions you learn as vocabulary.
The registers, in six lines
- the ます form, the ordinary polite verb ending, and the register a learner should live in for the first year. It is correct with strangers, colleagues and shopkeepers.
- です and である, the polite and the written plain copula. Newspapers and essays use the second, which is why written Japanese can look blunt.
- plain form is for friends and writing, and using it with a stranger is a real social error rather than a small informality.
- 尊敬語 and 謙譲語, respectful language and humble language. The first raises the person you are speaking about and the second lowers yourself, and both are used in the same conversation about the same action.
- いらっしゃる raises the other person, replacing the ordinary verbs for to be, to come and to go all at once. Keigo often swaps the whole verb rather than adding an ending.
- the wrong register is worse than a wrong word. A grammatical error is heard as foreign; a register error is heard as rude, and that asymmetry is why this is a cluster rather than a footnote.
The choice is about the listener, and then about the referent
The formality axis is decided by the ending on the verb, at the very end of the sentence, so it cannot be avoided and there is no neutral setting: whatever you say, you have said something about the distance between you and the person listening. Beginners are taught the polite form first, correctly, because it is safe with strangers, and then discover that everything in a drama or between friends is in the plain form they were told to leave for later.
The other two axes are about the person you are talking about, and this is where the genuinely surprising rule lives. Japanese groups people into inside and outside, and the boundary moves with the situation. Talking to a customer about your own manager, your manager is inside your group, so you use the humble forms about him, not the honorific ones, however senior he is. Talking to a colleague about that same manager, he is above you and takes the honorific forms.
Nothing in a European politeness system prepares you for that, because it is not about rank at all. It is about which side of a boundary the two people are on, and the boundary is redrawn every time the audience changes.
The learner who never leaves the polite form
Here is the stall, and it is social rather than linguistic. The polite form is safe, it is what the course taught, and it is never wrong in the sense of being ungrammatical. So a learner stays in it, with everybody, for years.
What that does is hold people at a distance. In Japanese the move to plain form is how a relationship becomes closer, and a person who keeps using formal endings with a friend is saying something, and what they are saying is that this is not a friendship. It is invisible to them and entirely visible to everybody else, and nobody will mention it, because mentioning it would be rude. The exit is to notice which form the other person is using and to follow, which is the same rule that works for address forms everywhere and is unusually consequential here. Getting somebody to tell you when to switch is exactly the kind of thing a paid hour is for, in what a teacher is worth, and what you can do alone.
Before choosing the verb
Which side of the boundary is the person you are discussing
One question, asked freshly for every conversation, because the boundary is redrawn by who is listening.
- Inside your groupHumble formsIncluding your own manager, your own company, your own family
- Speaking to a customer about a colleague
- Speaking to a stranger about your family
- Rank inside the group makes no difference here
- Outside your groupHonorific formsThe customer, the stranger, and anybody above you within your own side
- Speaking to a colleague about a manager
- Speaking to anybody about a customer
- The default when in doubt with a stranger
The boundary is situational rather than fixed, which is the part that has to be practised rather than learned. The same three people produce different forms depending on which two of them are in the room.
Two ways to hear the switch happen
Japanese television drama is the material, watched for register rather than for plot. Pick a scene with two characters who know each other and one with a customer, and listen to the endings rather than the content. It replaced the textbook dialogue, which is written entirely in one register for teaching reasons and therefore never shows the thing this page is about, which is the switch. Free wherever you already watch, and the useful exercise is to pause when a character changes form and work out what changed in the room.
A model will restate a sentence at several politeness levels, which is genuinely useful for seeing the machinery: give it one sentence and ask for plain, polite and honorific versions side by side. It replaced needing a teacher present for every small question. Free at this level. The limitation is exactly where the difficulty is: it will show you what each form looks like and it will not tell you which one is right in your situation, because that depends on facts about your relationship that it does not have.
The mistake: treating honorifics as extra politeness
Honorific and humble forms are not more polite versions of the same verb. They are different verbs, or different constructions, that encode who is above whom, and using an honorific form about yourself is not excessive politeness but a category error that a listener will notice immediately.
The practical route through is to learn a small number of them as pairs and stop there for a long while. There is an honorific and a humble verb for each of the common actions, and the set that matters in ordinary life is short: to go, to come, to say, to do, to eat, to see. Those cover most of what a customer facing conversation needs. Attempting the full system before that set is automatic produces sentences that combine forms in ways nobody says, which is a distinctively learner error and one of the few here that a Japanese speaker will actually correct.
What the ending is carrying
The politeness is decided in the same syllables as the tense and the negation, at the very end of the clause, which is why a Japanese sentence commits so late and is described in particles, and a verb that waits at the end. Those endings are written in hiragana attached to the kanji, so the script is showing you where the register is, in ninety two symbols, and the fortnight it takes. Register also runs through the vocabulary on a separate axis, and the two combine, in native words, Chinese readings, and English borrowings. And the honorific verbs are separate items that have to be stored as pairs, in readings, radicals, and an order that makes them stick.