This book may be one of the more important books I didn't read when I was young. I'm older now and it is not too late to read it. I'm surprized that along my education, I didn't become familiar with Pepper before.
Right now, I'm reading it with enthusiasm. And have the notion that the implications of the conclusions that Pepper draws are more important than most people realize.
As soon as I finish reading it, I will read the review by S.C. Hayes in the Journal of the Experimental Analysis of Behavior (1988).
A book I did read when I was a young man was "The Wisdom of Insecurity" by Alan Watts. I have a feeling that these two books have much in common.