My understanding of は vs が from the perspective of a programmer
My understanding of は vs が from the perspective of a programmer
Inspired by some concepts in programming recently I've come up with the idea that は marks an environment and が marks a variable inside an environment.
Environment and variable:
An example of environment:
猫は
┌───────────────────┐
│ E: cat │
│ │
│ │
│ │
│ │
│ │
│ │
└───────────────────┘
This is an environment with the name 猫.
Many things can exist inside this environemnt:
┌───────────────────┐
│ E: cat │
│ ----------------- │
│ behavior nyan │
│ │
│ cute liquid │
│ │
│ mouse ... │
└───────────────────┘
An example of variable:
猫が
v: cat
This is just a variable with the name 猫.
私は猫が
┌───────────────────┐
│ E: I │
│ │
│ │
│ │
│ │
│ │
│ v: cat │
└───────────────────┘
This is the depiction of an variable with the name 猫 inside an environemnt with the name 私.
Some sentences
Sentence 1: 猫が好きだ
This sentence can have any of following meanings according to context
a) Generally speaking, cats are liked [猫が好きだ]
b) As for me, cats are liked (-> I like cats) [私は猫が好きだ]
c) As for ? (someone or something according to context), cats are liked [◯は猫が好きだ]
a)
v: cat───────► liked
b)
┌───────────────────┐
│ E: I │
│ │
│ │
│ │
│ │
│ │
│ v: cat──┼────► liked
└───────────────────┘
c)
┌───────────────────┐
│ E: ? │
│ │
│ │
│ │
│ │
│ │
│ v: cat──┼────► liked
└───────────────────┘
Sentence 2: 猫は好きだ
This sentence can have any of following meanings according to context.
a) Generally speaking, as for cats, everything about cats is liked. [猫は好きだ]
b) Generally speaking, as for cats, ? about cats is liked. [猫は◯が好きだ]
c) As for me, as for cats, everything about cats is liked. (-> I like cats) [私は猫は好きだ]
d) As for me, as for cats, ? about cats is liked. [私は猫は◯が好きだ]
a)
┌───────────────────┐
│ E: cat │
│ │
│ │
│ │
│ │
│ │
│ ├───────► liked
└───────────────────┘
b)
┌───────────────────┐
│ E: cat │
│ │
│ │
│ │
│ │
│ │
│ v: ? ──┼───────► liked
└───────────────────┘
c)
┌───────────────────────────────┐
│ E: I │
│ │
│ │
│ ┌───────────────────┐ │
│ │ E: cat │ │
│ │ │ │
│ │ │ │
│ │ │ │
│ │ │ │
│ │ │ │
│ │ ├──┼────► liked
│ └───────────────────┘ │
└───────────────────────────────┘
d)
┌───────────────────────────────┐
│ E: I │
│ │
│ │
│ ┌───────────────────┐ │
│ │ E: cat │ │
│ │ │ │
│ │ │ │
│ │ │ │
│ │ │ │
│ │ │ │
│ │ v: ? ───┼──┼────► liked
│ └───────────────────┘ │
└───────────────────────────────┘
Sentence 3: 猫好きだ
I think here 猫 can be either an environment or an variable.
Environment & variable vs topic & subject: I think this environment model explains things betther than the use of the terms "topic" and "subject", at least for me.
I took inspirations from following sources:
a) Lesson 3: WA-particle secrets schools don't ever teach. How WA can make or break your Japanese (by Cure Dolly)
https://www.youtube.com/watch?v=U9_T4eObNXg&list=PLg9uYxuZf8x_A-vcqqyOFZu06WlhnypWj&index=3
b) Environment model in "Structure and Interpretation of Computer Programs"
I am certainly no expert in Japanese it's been more than 20 years since I lived there.
But one of my ways of understanding は and が is like in them to the articles "the" and "a". The former is talking about something that has not been mentioned before, or is unique. The latter is referring to an object that the listener knows.
To use your programming analogy, maybe it's like differentiating between an object and a class.
I personally had one or two issues with the video you used. I'm not sure they were being literal when they said は means "as for". は doesn't have any meaning, it has a function. Translating it this way can help people understand how は works within the sentence, but I've also seen it confuse people too. I once saw a post from someone who said 私は難しい incorrectly thinking it meant "It's difficult for me."
Some of the things you mentioned also weren't accurate.
a) Generally speaking, cats are liked [猫が好きだ] b) As for me, cats are liked (-> I like cats) [私は猫が好きだ]
Sentence B is correct. Sentence A however is just sentence B with the subject/topic omitted. You'll have to infer the it from the context, but it will be "I" in most cases. I don't think there will be any context in which it will be understood as cats being generally liked by everyone.
a) Generally speaking, as for cats, everything about cats is liked. [猫は好きだ] c) As for me, as for cats, everything about cats is liked. (-> I like cats) [私は猫は好きだ]
There are a few issues here that are a little misleading. は好き can be used like this, but in my experience of looking at sentence from native Japanese speakers, it's mostly only used in the following three ways:
- Comparisons, for example 私は猫は好きですが、犬は好きではありません (I like cats, but I don't like dogs.)
- Together with a conjunction like ですが、ですけど、でも, for example 私は猫は好きですが、飼ったことはありません (I do like cats, but I've never had one.)
- Together with になる, for example 私は猫は好きになれませんでした (I wasn't able to become a cat lover.)
Number 2 and 3 can be replaced with が, but は is preferred for number 1.
私は猫が好き also doesn't quite mean you like everything about cats. It's the same as saying you like cats in English, you're making a general statement without specificially identifying what you like about them. I like everything about cats is closer to 猫の事が好きです or 猫の全てが好きです.