On an early date with my now wife she spent an entire subway ride to Queens telling me about Montessori education methods and how it made her the person she is. I recounted that when I was in first grade I was punished for interrupting the class by having a cardboard box put over by desk, so nobody could see me, and that that made me the person I am.
So two passing tests in one convo: she was impressively interested in things that matter (I was already infatuated with her) and she was not put off by my bullshit.
You won’t know, they age like a fine wine - haven’t you heard? You will see very different facets of their personality- before you’re married, after you’re married, after you’ve had kids, after she stops being able to have kids, after the kids have gone off to college.. they are all the same person underneath it all, but you won’t know, you can’t.