Full Idea
The means by which platonic objects are simulated is existential metaphor. Numbers are conjured up as metaphorical measures of cardinality.
Clarification
Cardinality answers 'How many?'
Gist of Idea
Platonic objects are really created as existential metaphors
Source
Stephen Yablo (Apriority and Existence [2000], §12)
Book Reference
'New Essays on the A Priori', ed/tr. Boghossian,P /Peacocke,C [OUP 2000], p.214
A Reaction
'Fictional' might be a better word than 'metaphorical', since the latter usually implies some sort of comparison.