The first really big health issue is a word that Murray Schafer coined: "schizophonia." It's a dislocation between what you see and what you hear. So, we're inviting into our lives the voices of people who are not present with us. I think there's something deeply unhealthy about living all the time in schizophonia. The second problem that comes with headphone abuse is compression. We squash music to fit it into our pocket and there is a cost attached to this. Listen to this -- this is an uncompressed piece of music. And now the same piece of music with 98% of the data removed. I do hope that some of you at least can hear the difference between those two. There is a cost of compression. It makes you tired and irritable to have to make up all of that data. You're having to imagine it. It's not good for you in the long run. The third problem with headphones is this: deafness.