Full Idea
Suppose I say that I have given up precisely three beliefs since lunch. An over-coarse individuation could reduce the number to two, and an over-fine one could raise it to four.
Gist of Idea
How do you distinguish three beliefs from four beliefs or two beliefs?
Source
Willard Quine (Propositional Objects [1965], p.144)
Book Reference
Quine,Willard: 'Ontological Relativity and Other Essays' [Columbia 1969], p.144
A Reaction
Obviously if you ask how many beliefs I hold, it would be crazy to give a precise answer. But if I search for my cat, I give up my belief that it is in the kitchen, in the lounge and in the bathroom. That's precise enough to be three beliefs, I think.