不/没
bù / méi
不 is a door you closed; 没 is a footprint that was never made
The picture 不 is you pulling a door shut. 没 is looking back down the road and finding no footprints. 不 is about intent; 没 is about traces. 不去 is my own will — I'm not going; 别去 is a brake put on someone else — don't go. One closes my own door, the other stops your feet.
Where the picture shows up in 不/没
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a door kept shut (habit, will)
我不喝酒。
wǒ bù hē jiǔ
I don't drink.
A glass sliding toward you, your palm going up to block it, and your head shaking
-
no footprints on the road behind
我昨天没喝酒。
wǒ zuótiān méi hē jiǔ
I didn't drink yesterday.
Going back over yesterday's table in your mind and finding not one emptied glass
If the didn't is about the past, it is always 没. 不喝了 would mean I'm giving it up from now on.
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a door shut ahead too
明天我不去了。
míngtiān wǒ bú qù le
I'm not going tomorrow after all.
Drawing a line through the plan written in tomorrow's box
The future has no ground for footprints yet, so 没 cannot be used there.
-
a stretch of road not yet walked
我还没吃饭呢。
wǒ hái méi chī fàn ne
I haven't eaten yet.
Dinner time long past and the rice bowl still sitting upside down
还没…呢 puts the weight on not yet.
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before 是 it is always 不
他不是我们公司的人。
tā bú shì wǒmen gōngsī de rén
He isn't from our company.
A finger running down the staff list and finding the name nowhere on it
The mirror rule: before 有 it is always 没. 不有 does not exist.
All of it in one picture
Saying you don't drink is a door you keep shut — 不 — and not going tomorrow shuts a door up ahead the same way. Not having drunk yesterday and not having eaten yet look back along the road and find no footprints, so both take 没. And the last one, 不是, closes the matter outright, which is why 是 always takes 不. One asks whether your will is shut; the other asks whether there is any trace of the thing having happened.