“You become who you know and where you go.”

As the New Year dawns, I find this quote stuck in my head. Which means it’s worth posting about.

We’ve all heard of Dunbar’s Number, the number of people you can have in your life, or at least the number you know well enough to call a friend. It’s around 150. That was the case for our Paleolithic ancestors, moving around in small bands (150 was about as many people as you could build trust with) and it’s still true for us today.

But I only recently learned that there is also a Dunbar Number for places. In our daily lives, because we are creatures of habit, there’s a finite number of spots we typically visit over and over.

It’s around 25.

That’s it. Our coffee shop, gym, friend’s places, rep cinema, whatever: it adds up to 25 places. We can explore beyond our usual trapline, but when we do we have to drop a place, to keep the number at 25.

The two Dunbar numbers came to mind when someone forwarded me a New Year’s piece in The Wall Street Journal by TV writer Rob Lazebnik. Turning 60, he felt he’d become stuck in a rut. Lazebnik is a Simpson’s writer/producer, so he’s plenty creative. But he found that his life outside his head wasn’t exactly newsworthy. He realized he wasn’t really going anywhere new or doing anything novel. He felt he’d stopped evolving, “and I think we all know what happens then — like the dodo, you stop flying, get fat and Dutch sailors eat you on their voyage home.”

So he pledged to become “less boring” in 2026 by doing 60 new-to-him things – one for each year of his increasingly grooved life.

Many of the items on his list are distinctly Big Day-like.

Go somewhere you’ve never been. (He attends a megachurch.)

Make something you’ve never made. (He makes a shirt – albeit badly.)

Get permission to do something that’s normally off-limits. (He makes an intercom announcement on a commercial plane.)

Lazebnik’s theory is that we need fresh inputs to have fresh insights. There’s only so much juice you can generate from endlessly mulching your own thoughts and memories. Bored people quickly become boring people. He has taken to heart something Bill Murray said: People become more charismatic and better storytellers when they are reporting from the front. That is, from their own experience. “You have to hear stories and you have to live stories,” Murray said. “You have to have a bunch of experiences and be able to say, ‘Here’s something that happened to me yesterday.’

That speaks to me. My daughter is forever telling me, You gotta get out of the chair, Dad. You’ve gotta be out in the world making things happen, or at least setting up the conditions for things to happento you.

Social science tells us that adding novelty to our life makes us happier. But I don’t think novelty is all that these interventions are about. The bigger game here is psychological richness.

This is a term coined by Shinge Oishi, a U of Chicago psychologist and author of Life in Three Dimensions. Novelty alone does not make a life of psychological richness; trying a new flavour of ice cream won’t leave you happier for very long. There needs to be an element of difficulty, even hardship – something to struggle with and overcome.

The best Big Days have this going for them.

We shrink or grow, as humans, in proportion to the psychological richness of our accumulated experiences. That is the only kind of happiness that really matters. The further we wander today, the more satisfied we will be tomorrow.

Go out there and make yourself interesting.