You haven’t eaten since breakfast.
By late afternoon, you’re tired and having trouble concentrating. Someone asks you a simple question and you become irritated. A problem you’ve been dealing with suddenly feels much harder than it did that morning.
You start wondering what’s wrong. Why am I so impatient? Why can’t I make a decision? Why is this bothering me so much?
Then you eat.
An hour later, the problem is still there. The person who irritated you hasn’t changed. Nothing has been resolved. But it doesn’t feel quite the same.
We often look for psychological explanations for psychological experiences. If we’re irritable, anxious, discouraged, unfocused, or overwhelmed, we look at what we’re thinking, what happened to us, what someone said, or what the situation means.
Sometimes that’s exactly where the explanation is. Sometimes part of the explanation is that we’re hungry. Or exhausted. Or in pain. Or getting sick. Or recovering from being sick.
The body isn’t simply where the effects of experience show up. It is also part of the conditions under which experience happens.
Pain uses attention. Fatigue changes how much effort ordinary tasks require. Poor sleep affects concentration and patience. Hunger can make it harder to think clearly. None of these stays neatly physical.
When the body’s condition changes, what we can pay attention to can change. What feels manageable can change. A decision, a conversation, or something unpleasant may require more from us than it would under different physical conditions.
This can make the same life look different from one day to another. A problem that seemed manageable yesterday can feel overwhelming today. Something you interpreted generously when you were rested can feel much more threatening when you’re already depleted.
The circumstances may be almost identical. The conditions aren’t.
We readily understand one direction of this relationship. A difficult experience can keep us awake. Conflict can leave the body tense. Worry can affect appetite or digestion. What happens in our lives can change what happens in our bodies.
The reverse is just as important. What happens in our bodies can change how we experience our lives.
Physical and psychological aren’t two separate systems taking turns affecting each other. They are different ways of describing what is happening within one person.
The body isn’t outside the pattern. It is part of the conditions in which the pattern unfolds.