Full Idea
Putnam claims that the Löwenheim-Skolem theorems indicate that there is no 'fact of the matter' whether all sets are constructible.
Gist of Idea
The Löwenheim-Skolem theorems show that whether all sets are constructible is indeterminate
Source
report of Hilary Putnam (Models and Reality [1977]) by Stewart Shapiro - Foundations without Foundationalism
Book Reference
Shapiro,Stewart: 'Foundations without Foundationalism' [OUP 1991], p.109
A Reaction
[He refers to the 4th and 5th pages of Putnam's article] Shapiro offers (p.109) a critique of Putnam's proposal.