First published in 1971, Professor Putnam's essay concerns itself with the ontological problem in the philosophy of logic and mathematics - that is, the issue of whether the abstract entities spoken of in logic and mathematics really exist. He also deals with the question of whether or not reference to these abstract entities is really indispensible in logic and whether it is necessary in physical science in general.

Hilary Putnam

Preface; Chapter I What Logic Is; Chapter II The Nominalism-Realism Issue; Chapter III The Nominalism-Realism Issue and Logic; Chapter IV Logic vs. Mathematics; Chapter V The Inadequacy of Nominalistic Language; Chapter VI Predicative vs. Impredicative Conceptions of Set; Chapter VII How Much Set Theory Is Really Indispensable for Science?; Chapter VIII Indispensability Arguments; Chapter IX Unconsidered Complications