not a fixed input (and if human beings are the makers of history at the same time that they are products of it) emotions are not explainable entirely in terms of their preconditions. Relationships with parents and childhood experiences of all kinds are no doubt factors. But they cannot be the full story. On this understanding, growing emotionally – becoming more powerful, more productive, and happier in one's life – requires that bourgeois understanding itself be engaged and challenged. But this engagement does not end with the critique of bourgeois science. The critique is one component of a practice (and for most people seeking help, not the first one to be encountered). What matters most is not that patients understand the critique in its entirety, but that they are getting therapeutic help from therapists who are actively struggling to express the critique in their practice. As Newman and his colleagues express it, "knowing better" is not the same thing as "being better". Even on the most sympathetic reading, The Practice of Method is a sprawling and frustrating work. Its insights are suggestive and intriguing, but will seem to some to be insufficiently developed. Yet here too (to see a strength, as well as a limitation) its form is expressive of its content. It self-reflexively practices method. It demands that the reader – if only qua reader – be an activist. On its own account, it is not a theoretical treatise, but a component of the practice of social therapy and, in fairness, cannot be judged except in relation to that practice. While provoking pretty much everybody, The Practice of Method is also an invitation. It invites readers (whoever they might be) to participate in "a change that is an understanding". Are such participants "revolutionaries"? A categorical answer to this question is rejected. The practice of method does not answer every question – to paraphrase Vygotsky, it only answers those that are raised by history. "Undecidable Emotions (What is Social Therapy? And How Is it Revolutionary?)" (Newman, 2003, Journal of Constructivist Psychology) This article seeks to illuminate a revolutionary approach to group therapy by an appeal to – of all things – twentieth century discoveries in science and mathematical logic. "Is the set of all sets that are not members of themselves a member of itself?" The paradoxical answer to this self-referential question (if it is it isn't and if it