Full Idea
A knowledge of 'how many' cannot be inferred from the equinumerosity of two collections; a numerical quantifier statement is needed.
Clarification
'There are two' is a numerical quantifier
Gist of Idea
To know how many, you need a numerical quantifier, as well as equinumerosity
Source
Jeffrey H. Sicha (Counting and the Natural Numbers [1968], 3)
Book Reference
-: 'Philosophy of Science' [-], p.410