[ndt]

"Programs don't write themselves."

Actually some do. Guess what this successful method of solving problems was inspired by?

[manwiththehands]

So where did these self-programming programs come from? Outer space?

[grey_whiskers]

Actually some do.

Slight exaggeration there.

They change over time and can be [insert buzzword verb here] so that the programs get better and better at solving some particular problem, or approach closer and closer to an extremum (see also Lagrange multipliers)...

but in the strict sense, they don't write "themselves" ab initio.

Cheers!