Giovanni da Palestrina

Giovanni Pierluigi da Palestrina  was one of the great composers of polyphony in the Renaissance period.  

Polyphonic Renaissance music is:

flowing (which is easier to sing)

has many parts that sing at once which are different, but also similar (how?!).

You could describe the style as flowing like the water in a river.  

Questions

Do you agree?  Is there any way in which it is not like a flowing river?