I remember riding in my parents’ car when I was around six years old. I don’t remember where we were going, but it was dark outside and I was very tired. I was leaning my head against the glass, feeling the vibrations of the car, and matching them to the patterns that I imagined to represent the sounds of the road.
A tow truck passed us and I noticed a chain dangling from the side. The chain was rubbing against the ground and it made red sparks as it went past. I remember understanding this instantly–something red happens when things rub against each other.
The next day, I saw a couple arguing at a store. They were yelling at each other at the checkout counter. In my imagination, I made the images that represented their words change from white to red.
Friction is always red.