Full Idea
If the life of some person, or something went differently than it does, nothing would stop us from saying that it would be another person, or another possible universe which God had chosen. So truly it would be another individual.
Gist of Idea
If someone's life went differently, then that would be another individual
Source
Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.07.14)
Book Reference
Leibniz,Gottfried: 'Philosophical Texts', ed/tr. Woolhouse R/Francks,R [OUP 1998], p.109
A Reaction
Plantinga quotes this as an example of 'worldbound individuals'. This sort of remark leads to people saying that Leibniz believes all properties are essential, since they assume that his notion of essence is bound up with identity. But is it?