Fascinating question, Steve. Your response to your friend is much as mine would have been.
I don't know the Empty Mind concept, but it sounds a child-like state in which the filters that adults use are inoperative. I don't know whether that's something to aspire to or not. My own childhood was a time of visual and olfactory wonder, but with hindsight it seems that it was chiefly 'macro' in perspective, much more obsessed with detail than my adult senses. I could be fascinated by the iridescent patterns of oil on a rainwater puddle, and neither notice the passage of time nor hear the lorry approaching.