If Jack succeeds in forgetting something, this is of little use if Jill continues to remind him of it. He must induce her not to do so. The safest way would be not just to make her keep quiet about it, but to induce her to forget it also.
Jack may act upon Jill in many ways. He may make her feel guilty for keeping on "bringing it up." He may invalidate her experience. This can be done more or less radically. He can indicate merely that it is unimportant or trivial, whereas it is important and significant to her. Going further, he can shift the modality of her experience from memory to imagination: "It's all in your imagination." Further still, he can invalidate the content: "It never happened that way." Finally, he can invalidate not only the significance, modality, and content, but her very capacity to remember at all, and make her feel guilty for doing so into the bargain.
This is not unusual. People are doing such things to each other all the time. In order for such transpersonal invalidation to work, however, it is advisable to overlay it with a thick patina of mystification. For instance, by denying that this is what one is doing, and further invalidating any perception that it is being done by ascriptions such as "How can you think such a thing?" "You must be paranoid." And so on.—R.D. Laing, The Politics of Experience (1967)
R.D. Laing was a British psychiatrist and author whose clinical practice focused on schizophrenia, and, more specifically, on schizophrenic perceptions of the world. Laing believed that "sanity" was merely a symptom of conformity to a narrow view of reality, and he was fascinated by the kinds of experiences that could let someone see beyond the restrictions of "normality."
The Politics of Experience includes a number of essays and conference papers by Laing, and the epigraph to The Female Man is lifted from a chapter that explores the "negation of experience." In it, Laing discusses how facts and truths can be made to seem like fictions when a person's experience is invalidated or denied.
"Jack" and "Jill" are well-known figures from nursery rhyme ("Jack and Jill went up a hill to fetch a pail of water…"), and Laing's discussion of their relationship isn't specifically feminist. In Joanna Russ's hands, however, the passage takes on new significance.
In The Female Man, women's anger is invalidated by those who benefit from patriarchy. Women who are vocal about their opinions and experience are labeled "extremists" by men like Ewing, and because they're made out to be nothing more than man-haters, bra-burners, ball-breakers, shrews, harpies, and bitter spinster lesbians who couldn't catch men if they tried, the reality of their experience is denied and the patriarchy can keep on keepin' on with the status quo.