Why was/is James Joyce's writing revolutionary for its time?

Question

I love his writing, but I don't know why he is considered one of the great fiction writers in English. Why was James Joyce's writing so "revolutionary" for its time? I know that at one time originally it was considered risque for some reason, but I could ask the same thing about Ernest Hemingway.

Answer 1

Just an opinion:

1) It's stream of consciousness

2) It's frankly and descriptively sexual

Compare it to Song of Solomon from the Bible. That was considered barely acceptable.