I recently watched the Gregory Peck film Twelve O’Clock High, and I’ve been meditating on it ever since.

Peck’s character takes command of a struggling bomber squadron in the fraught early days of World War II. The previous commander burned himself out, and the unit has lost cohesion. Peck has to bring it back.

In one of the scenes that has stuck with me most, Peck — who’s walking a very fine line between forging his men into a fighting team and pushing them over the edge — says that they have to grow all the way up. In other words, these kids have to commit themselves fully to the job, even unto death.

The haunting part of the scene is that Peck clearly understands what he’s asking. As a commander, he knows that kind of growing up is necessary. And, as a human being, he knows it’s a tragedy.

We have no shortage of cultural tropes about growing all the way up in extremis. But it makes you wonder: what does it mean to grow all the way up in a time of peace and plenty? What’s the impulse? It’s surely still necessary … but can it be less of a tragedy?

Our culture loves collecting credentials.

And many credentials are sold as a way to advance your career. Like the “You Must Be At Least This Tall” measure before the rollercoaster, a credential is an easy way for an external eye to size you up and determine that you might be OK on this ride.

Credentials have their place, just as stepping back from the day-to-day grind of work to study and reflect can be a great way to get ready for what’s next.

But, too often, credentialing culture — and student culture — gives in to the temptation to believe that another credential is sufficient preparation.

We act as if we can focus on credentialing and our careers will take care of themselves, when in fact it’s the other way round.

Amateurs try to turn pro at turning in papers. Professionals always get their papers turned in, but they know it’s not the main point.

A friend of mine told me that his child’s preschool calls Play-Do “therapy dough.”

It sounds ridiculous to call four-year-olds’ play “therapy.” But there’s plenty of therapy dough among grown-ups, too. Explicitly or implicitly, resorts, coaches, and friendships are all encroaching on what you might call the “therapy space.”

All those things and many more might be therapeutic, but therapy is a profession. And its education and licensing rules are in place for a reason.

As another friend of mine likes to say, “professionals get professional help.” If you need therapy, skip the therapy dough and get a therapist — the best one you possibly can.

Don’t play therapy. Just play.

You can torture yourself with that question forever.

Far better to commit to stretching a little bit beyond yesterday each day.

And, still more importantly, to forgiving yourself and stretching again when you inevitably fall short some days.

Because, at the end of the day, you are enough — and you can always be a little bit more.

Any work that happens in meetings is accomplished by talking.

But if work’s going to happen, it matters who’s talking. Even and especially if you are in charge, the purpose of the meeting is almost certainly not for others to hear the sound of your voice.

If you have something to add that will help the work get done, add it. Hiding your perspective when it’s valuable doesn’t help anyone.

But editorializing on others’ work when it’s their responsibility and not yours doesn’t help, either.

If the team needs to get unstuck and back to work, let them — or possibly help them — talk through the block. Otherwise, “DNT:” do not talk.

(If you just need to pass the word or make yourself heard, send an email.)

We all know that an object in motion tends to stay in motion, while an object at rest tends to stay at rest.

Much the same is true of people in a culture: some will be moving in a particular direction (perhaps your direction), and others won’t.

If you want to move the culture, you face an important decision. Are you going to build momentum by exhorting the people who aren’t already in motion, or are you going to add momentum to those who are already going in the right direction?

It’s easy to focus on the people who aren’t in motion, especially if they are many or noisy or both.

But inertia works. And it’s usually a better idea to work with it rather than against it.

The social networks that have made most of the news in the early part of this century are the public ones.

The revolution might not have been televised, but it was on Twitter, Facebook, and the rest.

And I’ll admit that those networks can be great for finding the others, spreading the word, or starting a movement.

But I predict that semi-private networks will gradually prove at least competitive with and in many cases more valuable than those that reach effectively everybody.

As we’re seeing, the public square is a noisy and chaotic place — especially when it’s global. Remarkable things happen there, to be sure, but they have to compete for attention amidst the crowd.

A classroom, a meeting hall, or a fraternity house has a different feel, and networks of influence have always flowed to and through these more-or-less-gated communities.

When everybody’s already in on the joke, you can reach the punchline a lot quicker. Tap tap — we wear the ring: that’s a powerful way to open a conversation. A lifetime of culture gets packed into a quick touch of metal on wood.

So yes, you could head down to the public square to create or join a movement. But it might be worth looking for — or building — a network with funny outfits, cherished traditions, and an alumni network.

Those networks don’t often make the news, but their members sure do.

Asking a lot of questions feels generous, but it’s often promiscuous. How is the recipient supposed to respond to all that feedback, which is sure to point in many directions at once?

If you’re going to put in the effort to give any feedback, it’s worth going the extra mile to do it with the generosity of focus.

If many questions spring to mind, prune by at least 50 percent.

If you’ve still got more than four, halve the number again.

Overwhelming someone because you can’t be bothered to focus is lazy-aggressive, not generous.

Leadership might be scary for you, but it’s brave and generous for the others.

However difficult it feels to lead yourself, you’d be surprised at how much harder it is for the others in the community.

Stand up, speak up, and lead. It might not work, but the community will appreciate your effort. They’re waiting for you.

Are you trying to expand your span of control or your span of influence?

Extending control is an industrial approach. It insists on imposing sameness by measuring and managing.

Expanding influence is an organic approach. It acknowledges that everyone’s span of control is actually quite small — and yet our span of influence can be quite large. Therefore, influencing others to control what little they can control in a way that builds the culture is a powerful, far-upstream form of influence.

Are you growing tomatoes that all look the same but don’t taste like anything, or are you cultivating heirlooms that look wacky but taste great?

Which would you rather be known for?