You're right. Mathematics is a program that runs in a brain, which is a wet computer. Subjectively, the distinction is useful. I'm never going to have a differ

You're right. Mathematics is a program that runs in a brain, which is a wet computer. Subjectively, the distinction is useful. I'm never going to have a different brain, and I won't outlive my brain, so for all intents and purposes, my brain is an eternal constant. Theorems that ran on my brain once have accomplished their goal of convincing and never need to be run again. They are immutable.