In Marx, such a subject is revealed, through what is implicitly a phenomenological interrogation of self-consciousness, to be a "social human being," i.e. the individual "powers" required to be a "transcendental subject" in Husserl's sense are socially "constituted" within social relations revealed in the same way to be "internal relations." So Butler's claim in "Contingent Foundations" (e.g. p. 9) that the idea of such a "subject" is necessarily inconsistent with the idea of the "subject" as socially constituted is mistaken. Even the potential to become such a subject, the potentiality that, for Marx, defines "human" being, is itself "socially" constituted, i.e. constituted by "internal relations."
In fact, Butler doesn't understand the ontological idea of "internal relations." One sign of this ("Contingent Foundations" pp. 5-6) is that she doesn't understand the Hegel/Marx idea of each stage of a historical developmental process as characterized by particular forms of feeling, thinking, willing and acting. This is part of the conception of the process as a set of internally related "educational" "stages in the development of the human mind." The particular internal relations that define each stage produce characteristic forms of feeling, thinking willing and acting, the final forms being fully rationally self-determined forms. Butler's own ideas illustrate this point since they have no logical space for internal relations, self- determination and final causation, a feature they share with the scientific materialism dominant, "canonical," in Western thought since the 17th century.
The "subject," the "agency," the "self-determination," that is Marx's "social human being" is not "constituted through exclusion, that is, through the creation of a domain of deauthorized subjects, presubjects, figures of abjection, populations erased from view." ("Contingent Foundtions" p. 13) It's constituted by internal social relations that provide to everyone what each "needs" to become and live as a such a being, "production of this being" is "the most total and universal possible social product."
Butler misinterprets the meaning of the idea of a "transcendental subject" by imposing on it an unquestioned interpretive framework that denies the Other, in this case Marx, the possibility of "contesting" this framework, of calling it into question.
Phenomenology in the sense of Marx, Hussel and Whitehead never reaches final "truth." It's a never ending project.
"In scientific investigations the question, True or False?, is usually irrelevant. The important question is, In what circumstances is this formula true, and in what circumstances is it false? If the circumstances of truth be infrequent or trivial or unknown, we can say, with sufficient accuracy for daily use, that the formula is false.
"Of course the unknown limitations to Einstein’s formulae constitute a yet more subtle limitation to Newton’s formula. In this way dogmatic finality vanishes and is replaced by an asymptotic approach to the truth.
"The doctrine that science starts from clear and distinct elements in experience, and that it develops by a clear and distinct process of elaboration, dies hard. There is a constant endeavor to explain the methodology of science in terms which, by reason of their clarity and distinctness, require no metaphysical elucidation. Undoubtedly it is possible to express the procedure of science with a happy ambiguity which can receive interpretation from a variety of metaphysical schools. But when we press the question so as to determine without ambiguity the procedure of science, we become involved in the metaphysical formulations of the speculative Reason." http://www.anthonyflood.com/whiteheadreason.htm
"The disadvantage of exclusive attention to a group of abstractions, however well-founded, is that, by the nature of the case, you have abstracted from the remainder of things. In so far as the excluded things are important in your experience, your modes of thought are not fitted to deal with them. You cannot think without abstractions; accordingly, it is of the utmost importance to be vigilant in critically revising your modes of abstraction. It is here that philosophy finds its niche as essential to the healthy progress of society. It is the critic of abstractions. A civilisation which cannot burst through its current abstractions is doomed to sterility after a very limited period of progress. An active school of philosophy is quite as important for the locomotion of ideas, as is an active school of railway engineers for the locomotion of fuel." (Whitehead, Science and the Modern World, p. 59)
"But precisely therein lay the true significance and the revolutionary character of the Hegelian philosophy (to which, as the close of the whole movement since Kant, we must here confine ourselves), that it once and for all dealt the death blow to the finality of all product of human thought and action. Truth, the cognition of which is the business of philosophy, was in the hands of Hegel no longer an aggregate of finished dogmatic statements, which, once discovered, had merely to be learned by heart. Truth lay now in the process of cognition itself, in the long historical development of science, which mounts from lower to ever higher levels of knowledge without ever reaching, by discovering so-called absolute truth, a point at which it can proceed no further, where it would have nothing more to do than to fold its hands and gaze with wonder at the absolute truth to which it had attained." http://www.marxists.org/archive/marx/works/1886/ludwig-feuerbach/ch01.htm
Ted