I would like to express my deep gratitude to my advisor, Professor
John Myhill, for his advice, encouragement, guidance and illuminating
conversations on intuitionism and other subjects. I owe a special debt
to Professor F. William Lawvere for his help and discussions which brought
substantial insights to my understanding of the subject of chapters 1-3.
It was through these discussions that the principles espoused in section
1.1. became clear to me.
Many other people helped improve my understanding of topics discussed
in this monograph. Conversations with A. Joyal on his construction of
spoiling local compactness of the reals (presented with his permission in
4.2) first brought a connection with Cohen forcing to my attention. I
have furthermore benefited from valuable remarks and suggestions of
S. MacLane, P. Freyd, A. Blass, S. Schanuel, M. Barr, G. Reyes, J. Duskin,
J. Isbell, M. Fourman, and R. Grayson.
Mrs. Janet Burns did an excellent job in typing an often clumsily
written manuscript with patience and skill.