Media Analyst; Documentary Writer; Author, Life, Inc.
The eraser. As well as the delete key, white-out, the Constitutional amendment, and all the other tools that let us go back and fix our mistakes.
Without our ability to go back, erase, and try again, we'd have no scientific model, nor any way to evolve government, culture, or ethics. The eraser is our confessor, our absolver, and our time machine.