By “essentially embodied Kantian selves,” I mean necessarily and completely embodied rational conscious, self-conscious, sensible (i.e., sense-perceiving, imagining, and emoting), volitional or willing, discursive (i.e., conceptualizing, judging, and inferring) animals, or persons, innately possessing dignity, and fully capable not only of free agency, but also of a priori knowledge of analytic and synthetic a priori truths alike, with egocentric centering in manifestly real orientable space and time. The basic theory of essentially embodied Kantian selves was spelled out by Kant over the course of slightly less than two decades, between 1768 and 1787, but above all, it flows from an empirical realist and metaphysical reading of the “Refutation of Idealism” that Kant inserted into the Postulates of Empirical Thought section in the 1787 edition of the first Critique. In my opinion, all rational but also “human, all-too-human” creatures like us are, synthetic a priori necessarily, essentially embodied Kantian selves. Let’s call that the essentially embodied Kantian selves thesis, or for short, EEKST. If EEKST is true, then it’s synthetic a priori impossible for the selves of creatures like us to exist independently of our own living organismic animal bodies or beyond the deaths of those bodies, whether temporarily or permanently, by any means whatsoever. Indeed, the very ideas of disembodied selves, their survival after death, and of human immortality, while minimally logically consistent, are in fact conceptually empty and incoherent, even over and above the synthetic a priori impossibility of such things, since the term “myself” indexically picks out an essentially embodied Kantian self, all of whose core features require grounding in a particular living organismic animal body. According to the recent and contemporary movement of transhumanism, the selves of creatures like us can not only exist independently of our bodies, as functional systems of representational content that are inherently able to be implemented or realized in digital-mechanical technology and uploadable to servers, but also to survive accidental or natural human death in server-limbo, then be downloaded into technologically enhanced partially mechanical humanoid bodies or even into wholly artificially-created completely mechanical non-humanoid bodies, survive in these new implementations or realizations for an indefinitely long time, repeat that process, and possibly even become immortal. Transhumanism is in fact metaphysically equivalent to Swedenborgianism, which Kant so effectively criticizes and wittily derides in his 1766 book, Dreams of a Spirit-Seer Elucidated by Dreams of Metaphysics. Moreover, and more importantly, if EEKST is true, then, just like Swedenborgianism, transhumanism is not only conceptually empty and incoherent, but also synthetic a priori impossible. And what’s more, it’s also existentially and morally reprehensible. In short, then, the belief in transhuman selves is nothing but a reprehensible noumenal fantasy or Hirngespinst.