This dissertation examines how the human bodymind has been seen as malleable by science, technology, and policy practitioners from the Eugenic era in the United States in the first half of the 20th century, to the future imaginaries of Transhumanists and technology innovators. I critique the main goal of these practitioners – to perfect the human bodymind and through that perfection, perfecting human society – as utopic, impossible, and amoral. I argue instead, that we are intra-dependent – dependent on and through each other and our ecological contexts. I ground this argument both in the lived experience of those whose bodymind arrangements go against our normative expectations – folks like disabled people, queer and transgender people, body modders, and more – and in the philosophical metaphysics of Karen Barad's Agential Realism. I argue that we can only produce a future where bodymind alteration is acceptable if we first value different bodymind arrangements. I argue both that we cannot consider ourselves individuals, separate from the world or each other, and that multiplicity of bodyminds is a generative, heterotopic (neither utopic nor dystopic), force toward which we ought strive through engaging intentionally with each other in care relations. / Doctor of Philosophy / An interdisciplinary examination of how science and technology has made possible bodymind alteration from the eugenics in the early 20th century until today. Particular focus is given to how futures were imagined by different groups (eugenics educators, regenerative medicine scientists, and transhumanists in particular), the practices used to realize these futures, and the ethics around the practices and beliefs that are often taken for granted. I also describe several communities (disabled people, body modders, otherkin, and more) whose bodyminds are decidedly non-normative in order to reveal practices of community, kinship, and resistance to power that illuminate the lived realities of having a different morphology. I argue that these communities reveal ways to value and include morphological difference that might bring about a Morphological Freedom in which we might all thrive.

La thèse présente une analyse du transhumanisme et de ses enjeux, en partant de l’examen de sa philosophie, l’extropianisme, ainsi que de son projet. La mission transhumaniste est d’élever la condition humaine en offrant à l’espèce humaine le pouvoir de vivre indéfiniment grâce aux progrès des technosciences, mais aussi de s’améliorer cognitivement pour devenir plus intelligente et plus heureuse. L’objectif de la thèse est de mettre au jour les fondements philosophiques qui constituent le socle de la rhétorique transhumaniste afin de comprendre son efficience et pour analyser les enjeux éthiques qui en découlent concernant notre rapport à la mort, à l'existence et au temps. Il s’agira également de revenir sur la façon dont les fondateurs du transhumanisme se sont positionnés au sujet de ces enjeux pour insister sur l’importance d’une connaissance approfondie des principes et des valeurs du transhumanisme et de sa complexité pour proposer une critique de son projet. / The thesis presents an analysis of transhumanism and its issues, starting from an examination of its philosophy, extropianism, and its project. The transhumanist mission is to elevate the human condition by giving the human species the power to live indefinitely thanks to the progress of technoscience, but also to improve cognitively to become smarter and happier. The aim of the thesis is to uncover the philosophical foundations of transhumanist rhetoric to understand its efficiency and to analyse the ethical issues that arise from it in relation to our relationship with death, existence and time. It will also be necessary to consider the way the founders of transhumanism have positioned themselves on these issues to insist on the importance of a thorough knowledge of the principles and values of transhumanism and its complexity to propose a critique of its project.