We always say that music is a language. If this is true, then, if language (the way we speak) are still evolving, then, music is also evolving too. Because time presses on forward, and so does music. Nothing stays where they are, unless we are dead. So until, then, arts, science will always moves forward. And this is exactly what Schoneberg did when he came up with the 12 tone row. It is the most original and revolutionary idea since Bach wrote two books of the Tempered Clavier. Bach was exploring the tonal key's region, and here we have Schoneberg to explore the other side - the "atonality" key region.
The idea of "EMANCIPATION OF DISSONANCE" is the opposite way of viewing tonality, because it's ATONAL. The theory that dissonance and consonance are all relative to one another in terms of ratio. Then,dissonance comes out of consonance, and vice versa.
The pitches are locators on score, and the interaction between pitches within a composition defines their being.
Tonal music was about balance between melodies and accompaniment. Atonal music concealed more questions. There are more music than just melodies, music is also in tented for descriptive images, create new atmospheric sphere, emotional stirs, sonority, reactions to a particular events, paintings, realities etc.
In fact, when a piece of composition maintained, or increased its tonal ambiguities, a consonance (in a tonal sense) would in fact becomes a dissonance, because there are more dissonance than consonance. Also, when our ears are tuned into the most obvious, and familiar sound (dissonance), when an unfamiliar (consonance) sound occurred, we hear it as estrange or dissonance. Therefore, the dissonance and consonance ratio determines the "pitch" center.
I think music is a progression by reaction, and creation from raw materials that allow new music to emerge.
Stravinsky was first rejected the 12 tone row method when he embraced the neo-classical style. However, after Schoneberg's death, Stravinsky begin to composed with the 12 tone row in year 1955. This is an example of how composers are continually reacting to each other's innovation, and improved its creation.