“I don’t like the idea that I’m not in control of my life.” – Neo
There are many things we can’t control: the weather, sunspots, whether or not our favorite team wins.
There are some things completely under our control: our decision to download an app, or pick up the phone. To put on our running shoes and go (even if it is raining), to eat the cupcake or not. How we react to the spilt coffee.
To the Traditional Stoics, all things are in one of these two binary positions. Under our power or beyond us, the Dichotomy of Control.
But between these extremes of control lies the world of influence, an area Irvine discusses as the third part of the Trichotomy of Control. Your significant other tells you something not great, you quickly contemplate how to respond and make a statement. No matter what you say, they have their own free will (and biases and mental baggage and experience) and so decide how to react, and then you in turn do something. Neither of you are wholly in control nor wholly out of control but rather are interacting in an evolving dance that can go numerous ways.
This third area of influence covers essentially our entire lives, but it is the choices that we make that long term have the greatest influence as opposed to things beyond our control. It is our preparation (saving money, investing in our health, studying, etc.) that has the greatest bearing on our futures.