Mmm. Ray this is more philosophical. The voice is not an instrument. By definition an instrument is an external object altered or utilised to play sounds. A voice is just internal, natural and only metaphorically an instrument. Ok you sing and perform music... but it is not learning a skill to play an external note producing object.. but anyway, everybody is right and wrong. depending on the angle you come at! Some singers are trained or train themselves to use their metaphorical vocal instrument. I would call this one debatable (but no winner either side!) A good pub argument, that might end up in someone banging their head off the table in frustration, or possibly banging someone else's head off the table!