This essay aims at delving into the current theoretical relevance of Joyce`s (non-)fictional pronouncements as to the question of “the unity of subject” of the self, be it sexual, racial, or national, in conjunction with Derrida`s project of deconstruction of Western metaphysics. The focus of this essay is chiefly given on their resounding and profound critiques of purism rooted in the logic of modern notion of sexual identity and relationship among others. A careful examination will be afforded to their trenchant reflections on the notion of the unity of the subject. The unquestioned notion of Western metaphysics on binary opposition of sexual identity is a target on which both Joyce and Derrida do not draw back their critiques. Inasmuch as Joyce`s explication of the question of sexual identity resonates with the unfolding of contemporary discussions in gender theory and feminism, it cannot be unrelated to the seriousness and cogency of Derrida`s project of deconstruction. Joyce proffers a fundamental criticism of what Derrida may call the Western myth of origin, truth and purism, to name a few. A system of binary operation and distinction is at work in the phallogocentric mode of thinking. To make some headway in this difficult question, it may be useful to take a detour by posing the question of sexual and racial identity in Joyce`s pronouncements that lay bare what are unrepresentable in metaphysical concepts: the feminine, the unconscious, and the racial other. Joyce`s ambiguous and complex engagement with Irish nationalism and feminism is explainable in terms of his distance from any sweeping logic of simplification. Joyce`s thought-experiment on the question of sexual difference is closely intertwined with his deconstruction of the fixed ideas of immutable identity. He envisions a new notion of sexual and racial identity in process and relation, far from a fixed form.