Watch your thoughts
What we let into our brains quietly shapes our ideas and identities
👋Hello, my friend. A few thoughts this week on motivation, self-talk, and how what we let into our brains shapes us more than we think.
Let’s get into it!
A few weeks ago, I plugged a prompt into my AI assistant (stolen from Marc Andreessen) designed to challenge everything I said. No sugarcoating. Take the other side of every argument. Tear apart my assumptions.
I thought it would sharpen my thinking. And in some ways it did. But after a few weeks of starting my mornings with that kind of friction, I noticed something: it was pulling me in a direction that didn’t feel like me.
I’ve always thought of myself as a pretty optimistic person. I don’t normally walk around with a very harsh inner critic. But somehow I’d built a system that was feeding me negativity for an hour a day — and it was starting to color how I saw things.
It made me realize something simple but important: the voices you expose yourself to every day quietly shape your identity.
Podcasts, conversations, social feeds, AI systems, your own self-talk — they all become part of the architecture of your thinking.
The Energy You Feed Yourself Matters
Then I listened to two podcast episodes back-to-back that completely flipped the switch for me.
The first was David Senra interviewing Dana White, President and CEO of UFC. The second was a Founders episode on a young Arnold Schwarzenegger.
My reaction to both was immediate:
I want more of this mindset in my life.
Dana White doesn’t entertain self-doubt. He protects his belief aggressively. He ignores critics who’ve never built anything and defaults to action instead of hesitation. You can agree or disagree with how he operates, but he’s clearly built an environment around reinforcing conviction instead of feeding doubt.
But Arnold was the one that really got me.
I loved hearing him talk about weightlifting — seeing the results in his body, using that progress as fuel to push harder, getting radically specific about what he wanted to achieve.
He didn’t just say, “I want to get in shape.”
He decided he was going to become the greatest bodybuilder in the world.
And mind you, as a kid from a small town in Austria, this was a ridiculous concept.
But despite the fact that literally everyone around him, including his parents, thought he was crazy, he stuck with his vision.
Before he was Mr. Universe, he already saw himself as Mr. Universe.
He showed up to competitions with the attitude of:
That podium is mine. Everybody get out of my way.
But what struck me most is that this wasn’t just blind confidence or motivational fluff.
Arnold paired belief with obsessive tracking — photos, measurements, training logs — so he had evidence the program was working.
He built an identity and then reinforced it daily through action.
Identity Drives Behavior
That reminded me of James Clear’s idea of identity-based habits.
You don’t say:
“I’m going for a run.”
You say:
“I am a runner.”
Then you ask:
What does a runner do?
A runner trains consistently. A runner eats a certain way. A runner prioritizes recovery.
The identity drives the behavior.
I’ve been thinking about this across the different identities I’m trying to grow into:
Great dad
Great husband
Healthy and fit
Building something meaningful outside my day job
And it raises an interesting tension.
One of the recurring themes in the Founders podcast is that history’s greatest entrepreneurs often built extraordinary businesses at the expense of everything else. Relationships suffered. Health deteriorated. Balance disappeared.
Extreme success frequently comes from extreme imbalance.
So the question becomes:
Can you pursue ambitious growth across multiple areas of life without becoming consumed by just one?
Arnold as the Counterexample
Arnold might actually be the counterexample.
He took the lessons from bodybuilding — visualization, self-belief, relentless focus, measurable progress — and transferred them into Hollywood and then politics.
A kid from extremely humble beginnings became one of the highest-paid actors in the world and eventually the governor of California.
He didn’t dominate just one arena. He proved that success patterns can transfer.
And I think physical fitness may have more crossover power than almost anything else.
When you look better, you feel better. You have more energy. More confidence. You carry yourself differently.
It spills into every other area of life.
I actually sent the Arnold episode to my fourteen-year-old for exactly this reason. I’ve seen a version of this with my nephew, too. Once he got serious about lifting, there was a positive knock-on effect across his entire life.
What This Means for Me Right Now
For me right now, lifting is the thing.
It’s where I have the most energy and focus. And after listening to that Arnold episode, I realized I probably need to get more specific about what I’m actually trying to achieve.
Not just “improve body composition,” but a real measurable target.
I do believe I can get stronger. I do believe I can build more muscle.
But I want to get super specific. Exact body weight. Exact body fat %. Write that on my whiteboard, so I see it daily and start making decisions to get me to that very specific target.
And I suspect that if I approach it with the same level of specificity and intentionality Arnold brought to bodybuilding, the benefits will show up in places I’m not even expecting.
Reprogramming My Inputs
Which brings me back to AI.
I’m flipping the script on how I use it.
Instead of building a system designed primarily to critique and challenge me (I scrapped the prompt from Andreesen), I’m building one that reinforces the identities I’m trying to grow into.
Not as a sycophant — I still want honesty — but as a tool that nudges me with positivity.
I want to leverage the power of positive thinking alongside the power of AI to help put me in the right mindset every day to move closer to my goals.
I do think the environments that we put ourselves in (including our content diet) shape us more than we realize.
Your inputs become your thoughts.
Your thoughts become identity.
And identity drives behavior.
I’m trying to be more intentional about the things I repeatedly expose myself to — conversations, media, technology, even the tone of my own thinking.
Because over time, those inputs don’t just influence how you feel.
They influence who you become.
And if you want the two episodes that started this shift for me:
That’s it for this week. Thanks for reading!
Greg