Full Idea
Constuctivists link truth with constructive proof, but necessarily lack constructions for many highly desirable results of classical mathematics, making their account of mathematical truth rather implausible.
Gist of Idea
There are no constructions for many highly desirable results in mathematics
Source
James Robert Brown (Philosophy of Mathematics [1999], Ch. 2)
Book Reference
Brown,James Robert: 'Philosophy of Mathematics' [Routledge 2002], p.12
A Reaction
The tricky word here is 'desirable', which is an odd criterion for mathematical truth. Nevertheless this sounds like a good objection. How flexible might the concept of a 'construction' be?