So up until now I’ve completely left out how to conjugate the copula だ, instead opting to go over various particles, the different types of verbs, and how to turn those verbs into their negative forms. Many other explanations of Japanese grammar dive straight into conjugating the copula as one the very first lessons. However, in order to do this so early, the conjugations of the copula need to be essentially memorized as one-off grammar points without understanding why it conjugates the way it does. By waiting until now, hopefully, the copula conjugations will make sense in a much more systematic way as it builds upon earlier learned grammar.
- 好き（すき）・ Likeable / To like
- 大好き（だいすき）・ Lovable / To love
- 嫌い（きらい）・ Dislikeable / To dislike
- 大嫌い（だいきらい）・ Hateable / To hate
- 教師（きょうし）・ Teacher
だ as a contraction of である
The copula だ we learned way back in lesson 1 is really a contraction of the particle で and the verb ある “to exist”. Together, である therefore literally means “to exist as”, and it is easy to see how this combination was chosen to represent state of being. This etymology is important, because all of the conjugations for だ are based on the uncontracted form. The long form である is also still in use, largely in formal literary texts, such as newspapers (much, much more on this in a later lesson).
Negation ー ではない ・じゃない
As we learned in the previous section, the negative form of the verb ある is ない. Since the copula is comprised of the particle で and ある, the negative is formed by changing ある to ない. This gives us でない. However, people typically do not say でない, instead they say ではない, with the particle は combining with the particle で before the negated ある. This is because as we’ve seen, one of the jobs of the particle は is to show contrast and by inserting a は into the negative copula, we’re contrasting what something is not with what it is. For example, if we were to say:
This means “Takeshi is not an American”. The は in the negative gives the implication that even though Takeshi may not exist as an American, he does exist as something else (in this case, it is likely to be “Japanese”) and serves to emphasis the negation. This usage of は in the negative copula has become so idiomatic that it’s virtually obligatory and native speakers don’t give it a second thought.
To up the contrast even more, a は can also be inserted into the positive copula to create ではある as a kind of setup for an upcoming negation:
This sentence means “I do like sushi, but I do not love it”. You’re making an explicit point here to say that although you do enjoy sushi, you’re contrasting it with the fact that you do not love it, per se.
An important thing to note is that the particles では are often contracted to じゃ in colloquial speech, so in addition to ではない which often comes across as rather stiff, you will much more often hear じゃない in day-to-day conversation.
- たけしさんはアメリカ人じゃない – Takeshi is not an American
- これはペンじゃない – This is not a pen.
Inclusion – でもある・でもない
The copula can also be made inclusive by combining the particle で with the inclusion particle も in both the positive and negative forms, to create both でもある and でもない
- 私は小説家である。教師でもある (I am a novelist. I am also a teacher).
- 私は小説家ではない。教師でもない (I am not a novelist. I am not a teacher either).
The particles can also be split from the verb ある and listed multiple times in succession to group together multiple qualities in the same statement. For example, the above two example sentences could be reworked as follows:
- 私は小説家でも教師でもある (I am both a novelist and a teacher).
- 私は小説家でも教師でもない (I am neither a novelist nor a teacher).
Here we see でもない split into its constituent parts でも＋ない with successive uses of でも after both 小説家 and 教師 followed by a singular ある・ない at the very end.
This is also a useful pattern to know if you want to say something is “neither A nor B” or “both A and B”:
- 私は納豆が好きでも嫌いでもない (I neither like nor dislike natto).
This sentence literally translates to “As for me, natto is neither likeable nor dislikeable)”.