It seems to me that mental health might be defined as “the capacity for tranquility”. In some of my best moments I am doing nothing whatever. I can spend an hour just watching the sky. I am endlessly fascinated by clouds and wind and light. There is nothing unusual in this, of course, until you get to our contemporary society.
I wonder how long the perceptual lines can be when children are acculturated to expect constant change from the time they are infants. They grow up in front of TV’s, and migrate to text messaging. From what I hear, most college students anymore have attention spans measured in seconds, not even minutes.
Fractionalized attention could possibly be argued to be useful economically–although I would dispute even that–but it is absolutely inconsistent with the deepest and best human states, and the mental health the capacity to reach such states implies.