In their introduction, the Guerrilla Girls restate the question of “Why haven’t there been more great women artists throughout Western history?” into “Why haven’t more women been considered great artists throughout Western history?” In doing so, the question implicitly also states that there have been great women artists and that they have been overlooked. Thus, it sets the stage for the Guerrilla Girls to showcase examples of forgotten or dismissed female artists.
However, Nochlin argues that this common response is the wrong way to go about promoting women’s equality in art, and in fact, could very well to be detrimental since the response does not address underlying assumptions within the question (24). For example, Nochlin believes that the question holds an implicit answer – that “there are no great women artists because women are incapable of greatness”. Moreover, for the Guerrilla Girls’, I think another implicit answer for them is that because of barriers caused perhaps by men, by other women, or by institutions, female artists have not been able to be considered as great.
But for Nochlin, it’s not necessarily that women haven’t been considered great artists, but more that women have been unable to become great artists. Women have not been overlooked. They simply have not had as much opportunity as men to become great. Instead, her question is what are the concrete institutional support systems in place that prevent women from becoming ‘great’? And if there is not an essentialist difference between female and male greatness – like how Cixous might posit – since female artists seem to be more influenced by their contemporaries than by a thread of femininity, then what effects have institutions caused (24)?
I’m interested in how much blame we can place on institutional structures as the reason why women have not been able to ascend in Western art. Is it okay to say that women’s equality, not only in art but in any field, depends on institutions (25)? But aren’t the nature of these institutions shaped by men after all? I’m unsure of where the division between a group of men versus an institution formed by men lie. Does it even matter for women’s equality that we distinguish between men and an institution?
GENDER & SEXUALITY IN WORLD CIVILIZATIONS 
whoa, I think you are raising some really interest points here that I’ve not asked myself reading the texts. Now that I come to think of it, I can see how the term “institution” is masking the power relations and positing it to something that is harder to tackle with. I am not sure though if this was an intentional maneuver. Your last point about separating men and institution is also interesting because thinking of Butler’s account of gender, it isn’t just women who are oppressed. It’s also all the people of both genders and those in between. Everyone is regulated, implicitly and explicitly, to fit the gender norms, and the “institution” now seems like something that has grown out of male-dominance to something more close to species-dominance.
In terms of Nochlin’s argument too, I found her argument more appealing because she seems to take more into account of the context of becoming a so-called “great” artist, something that the Guerilla Girls seem to reject. Maybe women were less competent. Maybe they were artistic or creatively note-worthy. But there are other forces that led to this production of the “inferior” artist. For me, thinking along these lines help me understand the “so what,” and figure out what to do about it.
This makes me think about the Gilbert and Gubar reading–literature, like visual art, is an institution that has been dominated by men. Similarly, I think you could argue that Gilbert and Gubar’s theories in regards to anxiety of authorship could work here since women are also struggling to be taken as seriously as their male counterparts.