Full Idea
It is by means of things that we must distinguish one time and place from another, rather than vice versa.
Gist of Idea
We use things to distinguish places and times, not vice versa
Source
Gottfried Leibniz (New Essays on Human Understanding [1704], 2.27)
Book Reference
Leibniz,Gottfried: 'New Essays on Human Understanding', ed/tr. Remnant/Bennett [CUP 1996], p.230
A Reaction
This rests on Leibniz's relative view of space (as opposed to Newton's absolute view). If you need to re-identify a thing to individuate it, re-identifying the exact place or time seems impossible, but it is usually manageable with thing.
Related Idea
Idea 12506 A thing is individuated just by existing at a time and place [Locke]