mind wanderer

Unlike other animals, humans spend a lot of time thinking about what isn’t going on around them: contemplating events that happened in the past, might happen in the future, or may never happen at all. Indeed, mind-wandering appears to be the human brain’s default mode of operation. …

“Many philosophical and religious traditions teach that happiness is to be found by living in the moment, and practitioners are trained to resist mind wandering and to ‘be here now,'” Killingsworth and Gilbert note in Science. “These traditions suggest that a wandering mind is an unhappy mind.”