Intersubjectivity or Transindividuality examines several key moments of modern and contemporary philosophical thought, reading them in light of the alternative between the categories of intersubjectivity and transindividuality – between a philosophy that poses the space of interiority of the ego as a logical and ontological prius and a philosophy that radically conceives of relations as constitutive. The book’s chapters explore the different variations of this alternative, turning to Descartes, Leibniz, Kant, Hegel, Feuerbach, Stirner, and Husserl on the one hand, and Spinoza, Marx, Freud, Simondon, Althusser, Pêcheux, and Balibar on the other. These figures provide theoretical underpinnings for a transindividual political position, in which the critique of the category of intersubjectivity appears as the expression of a philosophy of possessive individualism.