In this chapter, I will explore the intersection of philosophy and childhood through the intriguing case study of J. S. Mill, who was almost completely denied a childhood—in the nineteenth-century sense of a qualitatively distinct period inclusive of greater play, imaginative freedom, flexibility, and education. For his part, Mill’s lack of such a childhood was the direct result of his father, James Mill (economic theorist and early proponent of Utilitarianism), who in a letter to Jeremy Bentham explicitly formulates a plan to raise his son as an experiment in the Utilitarian “science” of ethics. More specifically, although James Mill’s end was to create a near-superhuman champion of Utilitarianism, his means to that end included denying John access to other children and the Romantic poetry of his contemporaries. Despite this oppressive lack of a childhood, however, J. S. Mill went on to become perhaps the most influential social and political reformer in British history, especially in regard to gender relations through his groundbreaking work for women’s suffrage. This begs the central question of this chapter, namely how could a philosopher’s tyrannized childhood nevertheless lead to his later overturning of such tyranny in the political sphere?