"hands free set?" Oh, you're probably using a British English term for those telephones that are plugged into a person's ear. I don't know what they're called in American {USA} English.

When I first saw people talking on those phones, I wondered what in the world {or who in the world} they were talking to. But then I saw the black cord hanging down from their ear and figured that they were speaking to someone on a new fangled telephone.

But this man {and other people like him that I've seen over time} was definitely not talking on a telephone. He would turn to his side and wait and then respond and nod his head and make the kind of gestures that folks do when they're highly engaged in a conversation with at least one other person. In other words, it looked like the man was talking to another person, but I couldn't seen that person with my eyes.

Maybe some bums have better eye sight than 'regular' people. Or maybe their drinking or drugging puts them into another dimension which intersects this one.

Maybe other people can experience that dimension without drinking or drugging.