It is well-known that in the fifth of his Cartesian Meditations Husserl puts forth a theory of intersubjectivity. Most commentators of Husserl have read his Cartesian Meditations as presenting a theory of intersubjectivity whose basis is empathy, in the form of a process of constituting the sense of “other” in one’s own experience, as the primary origin of the intersubjective layer of experience. In this paper, I claim that the structure of intersubjectivity as Husserl presents it in the Cartesian Meditations is articulated as being governed by a logic of parts and wholes rather than that of a phenomenology of empathy, and that the articulation of this logic demonstrates that the transcendental ego is intrinsically intersubjective. My main philosophical claim in this regard is that the way Husserl’s account of transcendental empathy unfolds in the Cartesian Meditations implies a prior fundamental mereological structure, of which the individual transcendental ego is only a part. That is, the transcendental ego has an eidetic a-priori intersubjective structure, in the sense of being a moment of an intersubjectively structured transcendental whole. In this sense, rather than being a singulare tantum, it is more fitting to say that transcendental subjectivity is actually a plurale tantum.
My paper proceeds as follows. After a brief review of Husserl’s main claims regarding parts and wholes in the third of the Logical Investigations, I proceed to demonstrate how this conception of mereology applies to the realm of intersubjectivity presented in the Cartesian Meditations. In this framework, I first present an analysis of the essential relations between parts and wholes, which condition the process of recognizing other egos, that is, the mereological necessity, which makes possible and is manifested by I-thou relations. In Husserl’s terms, here the analysis focuses on the process, by which the other is originarily given in the ego’s “sphere of ownness,” through an “analogizing apprehension” on the basis of “pairing.” In this regard, I demonstrate that, given what we know about the a-priori laws of mereology, the passive synthesis of pairing itself already presupposes a unity of similarity in a plurality. Building on this conclusion, I then demonstrate that not only the consciousness of alter egos, but also the structure of transcendental intersubjectivity as such, Husserl’s “community of monads,” manifests a primordial mereological structure that is an essential and necessary condition for individual transcendental subjectivity as such. I conclude the paper by discussing the implications of such a view for our understanding of the sense, in which the transcendental ego is absolute and singular.