Mind wandering is the brain exploring the problem space. It’s where the brain goes when we are not intentionally focusing on something (or, to be precise, when those parts of the brain are not engaged in processes that are experienced as intentionally focusing on things, with the understanding that “experiencing” is also a product of the brain). Problem spaces being what they are, the human animal is not always in a cheerful mood when its mind is wandering. Not necessarily unhappy – but maybe a notch or two down on the happy-ometer. Except, perhaps, for those who love wandering in the problem space, following leads that may or may not bear fruit, discovering unknowns that had been unknown, making progress here and there (of the two-steps forward, one back sort – or vice versa). And coming to a better understanding of all the hurdles along the way. Finding patches of light that promise of greater clearings within the thicket of one's mind.

Of course, there will be plenty of dead ends and a tendency to keep trying the tried-and-false because the process has got stuck on repeat and we can’t yet see another way out of the rut. Then it’s good to take a break from all this exploring and reconnect with the perceptual world. The brain will keep working on the problems behind the scenes even when we are smelling the roses.

Strong opinion: a 6 on the scale of 0-10 does not constitute “unhappiness”, pace that highly over-rated paper, "A Wandering Mind Is an Unhappy Mind". For me, 6’s are fine. Nor do I care that people are slightly happier when perceptually engaged with their environment as opposed to when their attention is following the rabbits in their mind. Yes, engaging with the world, especially in ways that give pleasure, can get us out of a funk. And “being present” has its own rewards

But the title of this paper is overly categorical and misrepresents the actual findings. It seems that the authors wanted a catchy title, accuracy be damned.

Sure, happiness is a good thing. By that I mean that it seems worthwhile to want to occupy the 6-10 range on the happy-ometer more often than not.

It’s just that there is so much else that matters.