The book describes how the representation of certain psychological processes with a chain of heat engines allows modeling a large number of mental phenomena. This relation seems enigmatic in so far as we cannot find any analogues to heat engines in human body. Nevertheless, in his previous book, The Cosmic Subject, the author tried to link the chains of heat engines with objects physically existing in the reality. In his new book, the author chose a fundamentally different way. He revises the very concept of existing by considering that the ideal physical objects may also have a status of real existence. Mental phenomenology, according to the author, is a manifestation of existence of such ideal objects. Along this way the author deduces the main psychophysical laws and the Just Intonation set of musical intervals.