Full Idea
The concept of identity is central in specifying spatio-temporally broad objects by ostension. Without identity, n acts of ostension merely specify up to n objects. ..But when we affirm identity of object between ostensions, they refer to the same object.
Gist of Idea
To unite a sequence of ostensions to make one object, a prior concept of identity is needed
Source
Willard Quine (Identity, Ostension, and Hypostasis [1950], 1)
Book Reference
Quine,Willard: 'From a Logical Point of View' [Harper and Row 1963], p.68
A Reaction
Quine says that there is an induction involved. On the whole, Quine seems to give a better account of identity than Geach or Wiggins can offer.