Plato was somewhat unmerciful to many open ideas about music during his time. During the time period of Ancient Greece, he influenced other philosophers to also think about music and its limitations; by limitations I mean good and bad points about it. Ranging from the Republic to his Musical Idealism, Plato's thoughts and opinions on music are expressed.
In the Republic, Plato explained and contemplated music in the ideal state, the Laws; involving conclusions for the general good and bad for the people. Within the ideal state, Plato regards music as of great importance. Music should not be used to entertain people, yet used to "help in building up a harmonious personality and in calming the human passions." Education involving music helps one find their soul and grasp on to it; this is derived from certain rhythms combined with harmonia. Even though Plato believed that harmonia and rhythm were of great importance for the soul, he made it very clear that harmonia and rhythm were not to go out of "the text." In addition, within the Laws exists Plato's notion of music serving the state religion. Only in this situation are the instruments kithara and lyra allowed to be used. He spoke of how when something is sung and accompanied by an instrument, it should not be in harmony, but of the same tones, otherwise it would be of evil nature. He also banned the use of the modes except for two: Dorian and Phrygian. The Mixolydian and Lydian are too intense to service any good. The Ionian and Lydian are too relaxed to service any good. For some reason, Plato looked at the Dorian as "enforced" and the Phrygian as "voluntary." He also .
concluded that within the ideal city of the Laws that if music were to be performed on a contest level they would be judged by able, mature citizens to decipher whether a melody is appropriate or not; for the only person who was able to engage in free expression was the "civic poet.