A Psychological Study: Being a Contribution to the Foundations of a Theory of Knowledge
Including All the Essays, and Exhibiting the More Important Alterations and Corrections in the Successive Editions Published by the Author
Ratiocinative and Inductive, 7th Edition, Vol. II
The Nature of Human Brain Work. Letters on Logic.
Ratiocinative and Inductive, 7th Edition, Vol. I
A Modern Philosophy of Life Developed by Scientific Methods
MDCXC, Based on the 2nd Edition, Books 3 and 4
