Question about ている ていた for explaining state for something

Question

What is difference between 財布が落ちていた and 財布が落ちている? Both refer to the state of 財布, right? So, what is the difference?

(My main question is I want to know the difference between (が/は)～ていた and (が/は)～ている when they refer to the state of something)

Answer 1

財布が落ちている refers to the current state of the wallet. The wallet fell in the past, and you are seeing its result now.

財布が落ちていた is relatively more complicated because it involves two different time points in the past. 財布が落ちていた refers to the state of the wallet in the past. It describes what the wallet was like at the time of a certain event in the past. When you saw a wallet on the street yesterday, and want to report that fact now, you say 昨日道に財布が落ちていた. We are not interested in the current status of the wallet.

Let me reintroduce the diagram I made for another similar question. This uses other instant state-change verbs (帰る/割れる) as examples, but 落ちる is also an instant state-change verb. "Point of change" refers to the time when someone dropped the wallet, and the eye icon indicates the time you perceive(d) that fact.

Answer 2

The difference is the current state of the wallet.

If the wallet is currently falling or in a certain location (on the floor, etc..) as a direct result of having fallen, you use 落ちている. If the wallet was falling in the past and has already been picked up/removed from the state that resulted from falling (or was removed from the state of falling by being caught in midair), you use 落ちていた.

Note that if you just say 財布が落ちた you are simply specifying that the wallet fell at some point, but either you don't know whether or not it is still in the resulting state or it just doesn't matter enough to specify.