Well ok, I can't really be blamed for not understanding what you're saying when you whip out stuff that makes no sense...
...case in point.
Get yr expression on.
Well yeah if that's all she was saying I'd agree but she seems more to be expanding it to say that we never have or will act "rational" whatever that word means to her.
Well it's not really an arbitrary construct. Any word we develop to describe anything is an arbitrary construct if you want to play that game. As Chadd said, instincts are "pre-rational" but reflecting upon the reasons they developed would allow us to say they were "rational" responses to the...
I would agree with that but, to me at least, if you examined that majority of our "instincts" we would conclude that the reason they developed, in hindsight, reflects what we would call "rational."
EDIT: which is basically what you wrote in your edit.