Answer:
Every musical era had different priorities of these things, different things to pass on, different 'whats' and 'hows'. So in the first eight centuries or so of this tradition the big 'what' was to praise God. And by the 1400s, music was being written that tried to mirror God's mind as could be seen in the design of the night sky. The 'how' was a style called polyphony, music of many independently moving voices that suggested the way the planets seemed to move in Ptolemy's geocentric universe. A radical new move was need which in 1600 is what did happen and was the birth of opera, and its development put music on a radical new course. The 'what' now was not to mirror the mind of God, but to follow the emotion turbulence of man. And the 'how' was harmony, stacking up the pitches to form chords.
In short
the 1400s, 'what' was to praise god and the 'how' was a style called polyphony, music of many independently moving voices that suggested the way the planets seemed to move in Ptolemy's geocentric universe.
the 1600s, 'what' was to follow the emotion turbulence of man and the 'how' was harmony, stacking up the pitches to form chords.
Step-by-step explanation:
The top was words the speaker said in the TED.