I think technological civilizations start off with three stages.
Start off, mind you.
The first stage is learning how to draw straight lines.
All of of that civilization’s technology is bent toward understanding, describing, drawing, and building straight lines. It suffuses their art, their literature, their culture.
The second stage is learning how to draw curves.
In the second stage, a civilization comes to understand how unnatural straight lines really are. They start to recognize the curves and twists and bends in everything, from subatomic particle paths to the fabric of spacetime.
The third stage is where the concept of lines loses its meaning, where a civilization realizes that lines — whether straight or curved — are artificial constructs, describing only the tiniest sliver of reality. This goes beyond surfaces; it is an understanding of the interactions between everything.
After that, well, I can’t guess at the moment, but I think it’ll be interesting.
Naturally, I suspect de-evolution is possible as well, marked by the reversal of this path. But let’s not talk of bad news when the sun’s out and children are still laughing.