What is the thing that, if you don't believe it, you are not a feminist? Whereas everything else is debateable.
I am not exactly educated in feminism so this is mostly out of my head, but I would say that the key points are:
1 - The belief that everyone should be treated, valued, and respected equaly, and given equal opportunities in life, regardless of their gender
2 - The understanding that this is currently not the case
I can't think of anything else that is a must.
What do you think? Do you disagree with my "core values"? Would you add in anything else as an absolute?