The Ridgefield Diary (1944), Martinů's largest literary endeavor, consists of a complex of themes that circulate and overlap. Unifying his discussion is the idea that a musical work functions as a composite of organic relations. These relations, he shows, often get disturbed by romantic myths and faulty musical practices, and the distorted forms that musical works take lead to misconceptions among composers, performers, and listeners. In order to illustrate how musical relations function properly, he draws on the composer's creative process, building on the ideas he had established the previous year at Darien (see chapter 4). In his defense of musical relations, he also cites the experiences of performers—in particular, how they resolve technical issues in an effort to bring a musical work to life.

A related theme in his Ridgefield Diary is what I call his project for music education. Here Martinů's goal is to bring the common listener closer to the principles of musical craft from the perspective of the musician. A necessary step in this project is to debunk the notion that a composition embodies an emotional value that can be agreed upon universally, or that any two listeners can experience a work in the same way. In place of the romantic ideas about emotion that he found commonplace in musical culture, he suggests a new lexicon for emotion based on the technical decisions that composers and performers make.

Some of the most remarkable prose of his Ridgefield Diary comes in his discussion of how we listen to music and come to know musical works. He refutes the notion that a musical work has a fixed value, or that it can be defined in some kind of absolute terms. By contrast, he describes how each one of us acquires a unique knowledge of the work over time based on our individual experiences with it. His passages on listening, reception, and musical knowledge were probably influenced by the streams of phenomenology that were current during his time.

Reading through this substantial collection of essays from Ridgefield requires a fair commitment on the part of the reader. Thus I will provide the following synopsis, narrating his thoughts from his point of view in 1940s America.