Josef Rut studied violin at the Prague Conservatoire, graduating in 1951 with a performance of the Saint-Saens Concerto in B Minor. He was for thirty years a violinist with the Czechoslovak Radio Symphony Orchestra in Prague (1953-83) and for three years (1955-57) also in the Prague Chamber Orchestra without Conductor. He studied composition privately with Jaroslav Ridky (1952-54), and later for four years with PhDr. Emil Hradecky, who was mainly a theoretician and awoke in his pupil an interest in music theory. In trying to gain a more objective view of the problems of 20th-Century music, Rut came to reject the very old but still commonplace assumption that the laws and structure of music as heard are derived from sound as heard. This assumption underlies the whole development of theory from the once merely empirically accepted tone (Pythagoras) up to the contemporary idea of sound chosen arbitrarily, when the idea of searching for "a new sound" has naturally lost its meaning. Some composers of avantgarde type have returned to "traditional" musical material in their tonal organisation as well, but this return is epistemologically unsatisfactory, because it is not accompanied by any change in our view of the origins of music and its material.

The starting-point for Rut's new theory is the fact that music takes place in time. Relativistic physics, of course, conceives of time only in connection with space and movement, and not as existing independently of these, and it is contemporary physics that provides a basis, or indeed creates a necessity, for linking musical time with musical space and, naturally, music in this space-time dimension. The result is a musical space-time structure that varies with the quality of the movement. Chromatic movement and classical uniform space, the gravitational field of key and the curved space of diatonics, the geometry of key, the three spatial dimensions - these concepts only indicate the content of the problems involved; uncertainty in the placing of notes already brings us to quantum physics. The anthropological aspect of matters is a specific aspect of the musical; the method of research corresponding to music is not the method of physics, because the structure of musical space-time is not given, but we have first create it - naturally according to our capacities and in line with the outer world. Formulated in this way, the laws of musical movement spontaneously select only tonally organised tones from all the sound heard. This tonality is unavoidable. The relatively defined "at rest" position of the octave notes (the same tone at a double absolute pitch) is also the irremovable centre of the movement and time-space tonal structure, and the only given centre of common musical thought. Movement followed from different places, i.e. in relation to different tones of musical space, would appear different and common musical thought would not be possible.

Further development might be inspired by a twelve-tone scale with a diatonic groundplan: d-e-f# -g#-a-b-c#-d, and backwards d-c-bflat-aflat-g-f-eflat-d. The bi-key arises from two equal centres in the scale and on the tritone, i.e. from the same movement state of rest and uniform rectilinear movement (d-g#-d is the same as g#-d-g#). Harmonies arise from combinations of minor or major fifth chords. The relationships of the kinetic functions to the tonic are semitonal, because the opposite and equal tonic on the tritone is closer to the perfect fourths (i.e. the two gravitational fields) from the basic tonic. The twelve-tone bi-key requires no obligatory method of composition - its principle rationale is in the realisation of a new, purified and thoroughly diatonic order. Since 1964 the composer has written more than forty works in this bi-key.
The achievements of Josef Rut were noticed by American Biographical Institute (Raleigh), International Biographical Centre (Cambridge) and other publications.