—We never, ever use pencil because we never erase anything. You must keep the mistakes there. Mistakes are vital to every scientist's process. Just put a line through whatever you did incorrectly and keep going.

I wrote down this sentence and stared at it. It made perfect sense. The forgiveness built into this basic research philosophy—so simple and obvious—instantly validated my first semester in a way I could finally accept: everything led to this moment in this lab, the beginning of a new challenge of my own choosing. Put a line through it and keep going—I looked around to the other benches to see if anyone else registered the power of what she'd just said, but I was the only one taking notes, the only one nodding as my pen hovered over the page.