The only way the gender cult can convince people that changing one's sex is possible, by re-defining what 'sex' really is. That an individual and the surrounding society, can accept that one's sex isn't biological primarily, but is asigned by society; therefore one can reject this and 'choose' whether one is a man or a woman, or something imbetween or both, based not on biology, but on 'feelings' and ideas inside one's head.