I spent most of a Tuesday last month rehearsing an argument with someone who wasn't in the room.
You know the one. A message I was waiting on hadn't come. So I built the whole conversation in my head — their reply, my counter, their excuse, my devastating final word — and by lunch I'd lived through a fight that never happened and never did happen. The message, when it finally arrived, was three friendly lines. I'd spent four hours defending myself against a person who was, at the time, probably just at the dentist.
I lose more energy to that particular habit than almost anything else. Not to real problems — to imagined ones I have no power over anyway. And the thing that's helped most isn't a new app or a breathing technique. It's a single question a formerly enslaved Roman philosopher wrote down about two thousand years ago.
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The Oldest Anxiety Filter There Is
Epictetus opened his Enchiridion with one idea, and honestly he could have stopped there. Some things are up to us, he said, and some things are not. Our opinions, our efforts, what we choose to pursue and avoid — ours. Our reputation, our bodies, other people, outcomes, the past, the message that hasn't arrived yet — not ours.
Suffering, in the Stoic reading, is mostly what happens when we get the two categories confused. We pour enormous effort into things we can't control — what someone thinks of us, whether the launch works, whether the weather cooperates — and neglect the one thing we actually can: how we show up. Epictetus was blunt about the cost. Try to control what isn't yours to control, he warned, and you'll be anxious and disappointed. It reads like a man describing my Tuesday.
Here's what took me years to understand though: knowing the idea does almost nothing. I've known "focus on what you can control" as a sentence for as long as I can remember. It never once stopped me mid-spiral. The idea only started working when I turned it into a practice — something I actually run, on paper, when my chest gets tight. That's the part where AI turned out to be unexpectedly useful.
The Practice: Run Every Worry Through the Filter
The goal here isn't to think loftier thoughts. It's to physically sort your anxieties into buckets so your energy stops leaking into the ones that can't use it.
Step 1 — Dump it all out first. Before you sort anything, get every worry out of your head and onto a page — messy, unranked, unfiltered. "They haven't replied." "The numbers were down this week." "My knee." "The thing I said in 2019." Anxiety feels enormous partly because it's a fog. Writing it down turns fog into a list, and a list is finite.
Step 2 — Use three buckets, not two. Pure "control / not control" is a false binary, and pretending you have zero influence over things you can partly shape is its own kind of lie. Sort into three instead: in my control (my effort, my response, my next action), within my influence (I can affect the odds but not the result — most relationships and work live here), and neither (other people's choices, outcomes, the past, the future, the reply that hasn't come). Most of what tortures me lands in bucket three.
Step 3 — For "neither," practise the hand-off. For each item you can't control, name it and set it down — not by pretending you don't care, but by consciously handing it back to the category of things that aren't yours to carry. I have a line I say. It sounds almost too simple to work. It works anyway.
Step 4 — For the other two buckets, find the single controllable core. Every worry that isn't purely external has one small action buried inside it that is yours. "The launch might flop" isn't actionable. "Write the three emails I've been avoiding" is. Mine each control/influence worry for its one next action — then let the outcome go.
Step 5 — Make it a rhythm, not an emergency measure. I do a short version most evenings and a longer one on Sundays. Running the filter only during a panic is like only checking your mirrors during a crash. Done regularly, it stops being damage control and starts preventing the spiral in the first place.
Where AI Actually Earns Its Place Here
For years the barrier to this practice wasn't understanding — it was that when I'm anxious, I'm the least capable of sorting my own worries clearly. The spiral is the whole problem; asking the spiralling brain to calmly categorise itself is optimistic. What AI gives me is a neutral second party that isn't inside the fear with me.
Three prompts do most of the work. Use them with any assistant you like.
Here's a raw list of things I'm anxious about. For each one, ask me a question that helps me decide whether it's genuinely in my control, only within my influence, or neither. Don't sort them for me — help me see each one more clearly so I can sort it myself.
Notice the instruction not to do the sorting. The judgment has to stay yours, or the practice hands your own discernment to a machine — which rather defeats the point. Used well, it's a thinking partner, not an oracle.
For each of these worries that I've marked as "in my control" or "within my influence," help me find the single smallest concrete action that's actually mine to take. Not a plan — one next step I could do today.
I keep trying to control [X], which I can't. Help me write one honest sentence I can say to myself to hand this back — something that acknowledges I care about it without pretending I have power over it.
That last one produced my own hand-off line. Mine is: "I've done the part that was mine. The rest was never up to me." Yours will sound different, because it has to be true for you.
The Honest Caveat
Stoicism gets misused, and the dichotomy of control is the most misused piece of it. So, plainly: this is a tool for allocating your energy, not a licence to go numb.
"It's not in my control" can quietly curdle into "so I don't have to feel anything about it" — which isn't Stoic calm, it's avoidance wearing calm's clothes. The Stoics didn't teach the suppression of emotion; they taught not being ruled by it. There's a difference between grieving something you can't change and pretending it doesn't hurt. The filter is meant to stop you wasting effort, not to talk you out of your own feelings.
Worth saying plainly: It can also be used badly on bigger things — waving away injustice as "outside my control" is a way to excuse doing nothing about the parts that are within your influence. Most real situations have a controllable core. The practice is to find it and act on it, not to use the framework as permission to disengage.
Why This One Stuck
The version of me rehearsing that imaginary argument didn't need more information. I already knew the reply wasn't in my control. What I needed was a structure that made me stop and sort — and, on a bad day, a neutral voice to help me do it when my own was too loud.
That's the whole role AI plays here. Not wisdom. The Stoics had the wisdom two millennia ago. What I was missing was a way to actually run it when it counted — and that, it turns out, is a thing worth having a thinking partner for.