Full Idea
Mathematical abstraction does not have a lesser degree than logical abstraction, but rather another direction.
Gist of Idea
Mathematical abstraction just goes in a different direction from logic
Source
Paul Bernays (On Platonism in Mathematics [1934], p.268)
Book Reference
'Philosophy of Mathematics: readings (2nd)', ed/tr. Benacerraf/Putnam [CUP 1983], p.268
A Reaction
His point is that the logicists seem to think that if you increasingly abstract from mathematics, you end up with pure logic.