John Cage said this quote

“ After I had been studying with him for two years, Schoenberg said, In order to write music, you must have a feeling for harmony. I explained to him that I had no feeling for harmony. He then said that I would always encounter an obstacle, that it would be as though I came to a wall through which I could not pass. I said, 'In that case I will devote my life to beating my head against that wall. ”