In his book 'Oneself as Another' Paul Ricoeur articulates his philosophy of selfhood. Essential to his proposal is his claim that alterity is constitutive of selfhood as such. Through an examination of the tenth and final study of 'Oneself as Another' I will analyse Ricoeur's philosophy of selfhood and determine whether or not he achieves this intention. By exploring his account of the temporality of the self and its fundamental capacity for action I conclude that alterity, and its phenomenological correlate which is passivity, is not constitutive of selfhood. The thesis then examines the philosophy of Emmanuel Levinas. I conclude that his philosophy of alterity accomplishes that which Ricoeur cannot.