When you are young your mind and body are inseparable, the latter just a machine which, without having to think about it, carries out the mind’s wishes. The two are fused together, moving through life as a single unit, a horse and carriage. When we are old the mind and body separate from each other, we are aware of effort in asking the body to do our bidding. Things happen to the body that do not happen to the mind, which can only observe the effects from afar. The two no longer work together, the mind, still apparently young, seeks to do things the body can no longer do, like a driver trying to nurse a worn out car down a highway.