First Principles Thinking

I’ve re-read Sunil Pai’s “the senior engineer death spiral” several times this week. It’s very good. If you haven’t read it, start there.

It’s resonating with me because I think almost every senior engineer has felt some version of being stuck. You get good at what you do, then things change, and the experience you’ve built up can make it hard to approach things differently.

(Also, still getting over the fact that this is a different Sunil in software engineering.)

Pai talks about focusing on momentum instead of outcomes, and I fully agree. When I’m stuck, I break the work down to the smallest thing I can actually accomplish. Getting something done usually helps me figure out what to do next.

After sitting with his post, I kept coming back to first principles thinking.

I’ve been lucky to work with and manage a lot of great senior engineers. When I think about what made them great, I keep landing on the same thing: they seemed to know what needed to be done. There’s an intuition there that I’ve always admired.

Some of the best I’ve worked with came from customer support or services. Others taught themselves to code or started as designers or entrepreneurs. They took different paths into engineering, but they shared a habit of thinking from first principles.

They’d ask why we were building something and what it would do for the people using it. They could connect what was happening in the codebase to what was happening outside it. That understanding helped them keep things simple.

I think that’s another way to build the momentum Pai describes. Consider the simplest thing you could do first. It’s often enough.

Transitioning to the agentic era

I’ve had a lot of conversations with friends and coworkers about the shift to agentic development. The people who seem to be vibing with it are usually the ones who already think this way.

For me, this is the first major “simulation switch-up” where I’ve really had to embrace how much I don’t know. The engineers I see keeping up with what’s possible are willing to put what they know in a box for a while as they work with agents. They’ll try something before assuming an old constraint still applies.

Put it in a box

This is the hard part for me. Take your experience, what you’ve learned, and what you currently believe is true, and set it aside long enough to look at the problem again.

I still want to draw on that experience. But it’s easy to let a past project or a familiar technical limitation decide the answer before I’ve understood the problem in front of me.

When I step back and ask what we’re actually trying to do, why it matters, and how the pieces connect, I usually find more ways forward than I expected.

I’ve had a lot of conversations with folks trying to figure out what’s real with AI and what’s inflated. I think if you set your experience aside and look at what’s possible with fresh eyes, there’s a whole lot to admire, and a lot worth rethinking. For me, approaching it from first principles means starting with what we’re trying to do and asking how AI could help. It’s easy to get excited about the technology before you’ve answered that question.

That brings me back to the momentum Pai describes. I think first principles thinking makes working that way feel natural. When you truly understand what you’re trying to accomplish, it’s easier to take a small step, learn from it, and keep going. If you’re doing it right, working with agents lets that back-and-forth happen much faster. You get faster learning loops and more momentum, oriented around deep understanding. To me, that’s the new flow state.

Long Live Human Thinking.