Table of Contents

Preface

Van Dalen, D. ; Dijkman, J. G. ; Kleene, S. C. ; Troelstra, A. S.

p. 1
The scientific work of A. Heyting

Troelstra, A. S.

p. 3-12
The equivalence of two definitions of elementary formal system

Curry, Haskell B.

p. 13-20
A note on spread-cardinals

Van Dalen, Dirk

p. 21-28
Persistent and invariant formulas for outer extensions

Feferman, Solomon

p. 29-52
Attributes, sets, partial sets and identity

Gilmore, P. C.

p. 53-69
Existence in mathematics

Goodstein, R. L.

p. 70-82
Assertions depending on time and corresponding logical calculi

Grzegorczyk, Andrzej

p. 83-87
Relativization with respect to formulas and its use in proofs of independence

Henkin, Leon

p. 88-106
Functional interpretation of bar induction by bar recursion

Howard, W. A.

p. 107-124
Almost direct products and saturation

Jónsson, Bjàrni ; Olin, Philip

p. 125-132
Constructive mathematics as a philosophical problem

Lorenzen, P.

p. 133-142
Quantifier-free axioms for constructive plane geometry

Moler, Nancy ; Suppes, Patrick

p. 143-152
Binary generators for the m-valued and ℵ 0 -valued Lukasiewicz propositional calculi

Rose, Alan

p. 153-169
Axiomatisation indépendante des ensembles dénombrables de formules en logique intuitionniste

Reznikoff, Iégor

p. 170-187
Some thoughts on the history of mathematics

Robinson, Abraham

p. 188-193
Extending the topological interpretation to intuitionistic analysis

Scott, Dana

p. 194-210
New sets of postulates for intuitionistic topology

Troelstra, A. S.

p. 211-221
Lawless sequences of natural numbers

Kreisel, G.

p. 222-248