Platonist reasoning is the antithesis of constructionism.
Thanks for the clarification. In this short discussion I've seen at least three conflicting ways that people use the term "Platonism":
1. Platonism == Mathematical Realism.
2. Platonism == The belief in Ideal Horses, which "real" horses only approximate.
3. Platonism == Non-constructivism.
-- Kory