Reti was in contact with Schoenberg at the time of that composer's earliest atonal works, and in 1911 gave the first performance of his Drei Klavierstücke Op.11.
Reti's output also includes several volumes of piano pieces and songs, an opera (Ivan and the Drum), as well as symphonic and choral music.
For Reti, "the different movements of a classical symphony are built from one identical thought", [TPM, p. 13] and the composer "strives toward homogeneity in the inner essence but at the same time towards variety in the outer appearance.
[TPM, p. 13] Reti's way of showing 'maintained substance' would usually involve constructing a music example which juxtaposed a number of contrasting themes; the 'homogeneity in the inner essence' was represented by the notes printed at full size; the 'variety in the outer appearance' would be relegated to small type.
Reti's analytical procedure is best understood concurrently to the work of other contemporary German analysts of the time such as Schenker and Schoenberg.
The preoccupation the three aforementioned theorists had with such procedure stems from a metaphysical belief that the works of the "great masters" (as exemplified in the First Viennese School) were unified thematically often, from a single idea.