In "Gender Trouble," Judith Butler describes the ways in which gender and sexuality are culturally and socially constructed. She argues that the strict binary opposition of male/female and the cultural tradition of emphasizing heterosexuality as the so called "normal" sexual preference has limited the very concepts of male and female. She notes that those who do not fit within these "normal" identities (homosexuals, trans-gender, etc.) have been deemed as outcasts and therefore these outcast identities are labeled "abnormal." Clearly, Butler takes issue with the "normal" and "abnormal" labels. But she goes much further. Rather than trying to define the female roles and/or the outcast groups in order to support their essential identities, she seeks to free up the notion of identity altogether.
Since she suggests that gender is a cultural performance, Butler proposes to free up limitations of gender rather than establish rigid, inflexible identities of gender and the so called "normal" or "abnormal" categories. Butler would rather do away with such rigid categories, thus freeing up the concept of identity. And without such rigid categories, the "normal" loses its power of cultural superiority and the "abnormal" loses its stigma as "other" or outcast.
In terms of feminism, Butler argues that feminists had been misguided in attempting to describe a certain identity for women. She would prefer to determine the ways women can be rather than the way or ways women should be. A similar argument could be made for feminism. For Butler, gender is a performance; thus, it IS as it is created. There is no preestablished blueprint (outside of those limiting historical categories of male/female, heterosexual/homosexual. Just as Butler would not limit females to a strict, rigid identity, she would also prefer that feminism not be so rigidly defined. Therefore, Butler would not embrace a doctrine that says "a woman must be X" or "a feminist must believe in X,Y,Z." As feminism has developed, many feminists have embraced Butler's idea and consequently, there are many versions and doctrines of feminism. Butler frees up what identities can be by focusing on the performative aspects of identity.