What does it mean the worst battle you have to fight is between what you know from what you feel?

I think it means that one of the greatest struggles is balancing reality (what you know) and your own feelings (what you feel). This can be hard because sometimes our feelings can get in the way of our better judgement and we will have to "fight" to make sure that we are using our heads as well as our hearts to lead our lives. It can be hard to pick between what you know and what you feel. That's what I think the quote means. Sorry for the badly worded answer :/

If I was in a haunted house, even though logically, I see no reason to believe ghosts,, at the time, I would be very jumpy and nervous anyway and would frighten easily, especially if it was something I couldn't see/explain right away.

IDK if you understand that-I guess it kind of depends on how strong your emotional sense is.

in my military time we were told to think about what is on the other side of that door, is it a guy with a weapon ready to shoot us as we opened that door or is it a family cringing in terror from the sound of gunfire so you got to tune your thoughts to what you know is behind that door and what you feel

is the right move you make in that matter .