Hilary Putnam
Abstract
In 1922 Skolem delivered an address before the Fifth Congress of Scandinavian Mathematicians in which he pointed out what he called a "relativity of set-theoretic notions". This "relativity" has frequently been regarded as paradoxical; but today, although one hears the expression "the Lowenheim-Skolem Paradox", it seems to be thought of as only an apparent paradox, something the cognoscenti enjoy but are not seriously troubled by. Thus van Heijenoort writes, "The existence of such a 'relativity' is sometimes referred to as the Lowenheim-Skolem Paradox