Disclaimer: This post is not intended to state an official MRM position, nor to blame women or gynocentrism. This is my attempt at determining a root cause of sexism, inspired by various MR contributors (largely girlwriteswhat) and to contrast it to the equivalent Feminist theory (Patriarchy). As such it is an analysis of the way things are, in my opinion, without attaching value judgments to any causes.

In my opinion, both genders (I focus on the binary genders since they are the most common) face discrimination, but my MRM inspired theory and Feminism take fundamentally different views on how this discrimination came to be.

Feminism believes it originates from men (hence the Patriarchy) and a psychological tendency in men to control and dominate. As a byproduct of this women are discriminated against by being controlled and protected as a possession. Additionally, men are discriminated against as disposable in order to affirm their superiority over women and protect their "possessions".

My MRM inspired theory believes it originates from both men and women in the form of gynocentrism, a psychological tendency of both genders to protect and supply women (which for the majority of our history included children by extension). As a byproduct of this women are discriminated against by being controlled in order to keep them safe, and to incentivize men to protect and supply them (this byproduct effect of gynocentrism can be interpreted as the Patriarchy). Men are discriminated against as disposable in order to maintain protection and supply for women.

The end results of both theories are very similar, but how they got to those results suggest completely different courses of action to rectify the discrimination. The feminist theory suggests teaching men that they are not superior to women, women that they are not inferior to men, and everything will be fixed. My theory suggests teaching the same things, but that teaching those things alone are insufficient to rectify the problem (as they don't address the core issue). You also need to teach men that they are just as valuable as women, and teach women that they are not more valuable than men.

TL;DR feminism and the my MRM inspired theory see similar results, but attribute the cause of them to patriarchy and gynocentrism, respectively

Edit: I have fixed my very poor phrasing which led to misunderstandings. Please forgive me and give me your comments and opinions on my theory (check out girlwriteswhat for the main source of inspiration for my theory).