Everything in life has a negative side to it. This nasty fact has also left its mark on language, in the form of negative prefixes that will turn just everything into its opposite. Or spoil it some other way, by contradicting, denying, canceling, revoking or refuting it. Like English “un-” and” “in-,” “dis-” and “de-,” “non” and “no-,” Japanese has a number of forms that do this destructive job. And they do it quite well.
The most neutral negative prefix is 無 (mu, bu), used first and foremost to indicate the absence or lack of something. A figurative example is 無人島 (mujintō), a “no-people island” — that is, one that is uninhabited. Likely more familiar to city-dwellers is the term 年中無休 (nenchū mukyū, open 24/7 year-round), where 無 indicates the absence of holidays through the year.
Despite its negating function, 無 can generate quite positive expressions. In the world of money, for instance, it brings us consumer-friendly concepts like 無料 (muryō, free of charge) and 無税 (muzei, tax-free). And just as drivers aspire to a spotless record of no accident and no traffic violations (無事故無違反, mujiko muihan), goalkeepers try to keep a clean sheet (無失点, mushitten). The positive potential of negative 無 is perhaps best captured in the term 無事 (buji, literally “without a thing”), referring to all manner of states of safe-and-soundness.
The most puzzling use of 無 with a positive meaning occurs in the term 無洗米 (musenmai), where the prefix combines with the characters for “wash” and “rice.” Note that the resulting meaning is not that this rice comes unwashed, but that it doesn’t need to be washed in the first place. In other words, the product on offer is not non-washed but no-wash rice.
While lack of something does have its positive sides, the mere observation of absence can also convey some reproach or criticism. As linguists know, denying the existence of something (called “contradictory negation”) often results in claiming the opposite of that something (called “contrary negation”). A case in point is 無責任 (musekinin), where absence of responsibility effectively means irresponsible behavior. Other common 無 expressions with a clearly negative meaning are 無意味 (muimi, meaningless), 無駄 (muda, useless), and 無理 (muri, unreasonable, impossible).
A second major form for negation is the prefix 不 (fu, bu). Though to some extent overlapping with 無, it tends to state more openly that the contrary of something is the case. As a result, almost all 不 words have a negative meaning: 不平等 (fubyōdō, unequal), 不公平 (fukōhei, unfair),不機嫌 (fukigen, bad mood), and so on. Particularly nasty is the term 不細工 (busaiku), which castigates not only poor craftsmanship but also unattractiveness, particularly in women. Rather 不親切 (fushinsetsu, unkind), isn’t it?
An interesting property of 不 is that it often reduces the term-to-be-negated to one character. This gives us words like不満 (fuman) as the antonym of 満足 (manzoku, satisfaction), 不可 (fuka) as opposed to 可能 (kanō, possibility), 不便 (fuben) to lament the lack of 便利 (benri, convenience), and a couple of others.
A third important prefix is 非 (hi). It shares characteristics of both 無 and 不, but corresponds more closely to the English “non-,” thus marking some state of qualitative otherness. 非金属 (hikinzoku), for instance, refers to nonmetal objects, while 非常識 (hijōshiki) brands something as non-commonsensical. The idea of extraordinariness also figures in the terms 非常口 (hijōguchi, emergency exit) and 非常勤 (hijōkin, part-time [work]).
For everything in a state of “not yet” rather than just “not,” the prefix 未 (mi) can be an option. We find it in terms like 未定 (mitei, not yet decided) or 未婚 (mikon, unmarried). And if someone in Japan who is 二十歳未満 (hatachi miman, under 20) drinks, that qualifies as 未成年者飲酒 (miseinensha inshu, drinking under age). One rather unfortunate term from the 未 family is 未亡人 (mibōjin), a “not-yet-dead person” — that is, a widow. You needn’t be a feminist to not-like it.
These are the big four in Japanese negation, but there are many others that can do similar work: 反 (han), as in 反政府 (hanseifu, antigovernment), 抗 (kō), as in 抗がん剤 (kōganzai, anticancer drug), 逆 (gyaku), as in 逆効果 (gyakukōka, opposite effect), 誤 (go), as in 誤算 (gosan, miscalculation), 脱 (datsu), as in 脱原発 (datsu-genpatsu, phasing out nuclear energy), 否 (hi), as in 否決 (hiketsu, vote down), 違 (i) as in 違法 (ihō, illegal), 悪 (aku) as in 悪用 (akuyō, abuse), and ダメ (dame), as in ダメ親 (dame-oya, problem parents).
Given this large pool of items, it may sometimes be difficult to decide which one to put where. However, be sure you know your prefixes well, because if you do, there’s nothing you can’t do. Or, more precisely, nothing you can’t undo.