に
ni
One arrow, one point: に
The picture An arrow flying out and sticking into one spot. That single stuck point is に. に is the point the arrow lands on; で is the field the action happens on.
Where the picture shows up in に
-
the point in time
七時に起きます。
shichi-ji ni okimasu
I get up at seven.
An arrow sticking into the seven o'clock mark on a clock face, and eyes opening at that instant
-
the point you reach
会社に着きました。
kaisha ni tsukimashita
I've arrived at the office.
A toe touching down right at the front door of the office building and stopping there
-
the point something rests on
机の上に置いてください。
tsukue no ue ni oite kudasai
Please put it on the desk.
An object settling onto one spot on the desk and coming to rest there
に is where something is, で is where something happens: 会議室にいる versus 会議室で待つ.
-
the person it lands on
課長に聞いてみます。
kachō ni kiite mimasu
I'll ask the section chief.
Your question flying like an arrow and landing in the section chief's ear
-
the point you aim at
買い物に行きます。
kaimono ni ikimasu
I'm going out to do the shopping.
Walking out the door with a shopping bag, aimed at the shop
All of it in one picture
に is the one point an arrow sticks into. Land it on the clock face and you get 'at seven'; land it at the front of a building and you get 'arrived at the office'; land it on the desktop and you get 'put it there'. Land it in someone's ear and that person is who you ask; aim it at an errand not yet done and you get 'out to do the shopping'. Either way, what carries に is never a wide field — it is a single point.