This is not debate team. The point is not to frame the discussion so you can "win".
Whether you want to admit it, there are things you can never know. That's incontrovertible. You have two choices: you can throw your hands in the air and say "oh well I'll never know" or you can start to learn how to sense when other people have a depth of knowledge or experience that is unavailable to you, and use their knowledge to help you act in the world.
Many very bright people are constitutionally incapable of working this way. Unless they can reduce a concept down to first principles that are grounded in their personal experience, the concept is wrong to them.
To me, that's a huge epistemological limitation, and I think it will hamper your ability to grow intellectually. I have found that with certain things I had to first accept them and live with them, after someone I trust and respect, with different experience than I have, suggested they were true. Only later, after living with and applying the ideas, was I able to rationalize them.
This realization is the greatest gift Feminist theory has given me, as a thinker.