I was talking with some friends about some related questions today, and noticed that there's another lens on the role of choice in mindset dynamics, which is in the realm of self-fulfilling... beliefs? Stances? I'm not sure what to call them exactly, but basically the thing where to a large extent people who treat the world as hostile will encounter a hostile world, and people who treat the world as friendly will encounter a friendly world. Thus, since either belief is true for those who hold it, might as well choose the one you want. I've oriented to growth mindset like this, for sure. In some sense, arguably, this is even what a mindset is.