This is a short paper describing how a herbrandized functional interpretation can give a new treatment of some issues in classical second-order arithmetic. It is perhaps worthy of note that, in our interpretation, second-order variables are interpreted by finite sets of natural numbers.
Cite this article
Fernando Ferreira, Weak König’s lemma in herbrandized classical second-order arithmetic. Port. Math. 77 (2020), no. 3/4, pp. 399–408DOI 10.4171/PM/2056