Fernando Pessoa’s invention of the heteronym represents a singular moment in the history of subjectivity. Heteronymy is, as the name implies, an othering of oneself, an awareness of oneself but as other. The contrast with the pseudonym is deliberate: a pseudonym is a mask, a disguise intended, even if only ironically, to hide the true identity of the author. A heteronym is something else entirely: it is the author writing ‘outside his own person’ and in doing so transforming himself into an other I. A heteronym possesses agency, if only in the capacity to compose verse, and has its own expressive and experiential style. If transforming oneself in simulation into an other I is the core of the idea of heteronymic subjectivity, an equally important theme in Pessoa is that of depersonalization. Living through a heteronym, which from one point of view must certainly constitute an enrichment of experiential life, is paradoxically described in terms of a loss of self. Two distinct kinds of self-awareness are co-present in any act of heteronymic simulation: a heteronymic self-awareness which consists in an awareness of oneself as another I, living through a distinctive set of experiences, emotions, and moods; and what I will call a forumnal self-awareness, an awareness of oneself as hosting the heteronym, which is at the same time a place from which one’s experiential life qua heteronym can be observed and analysed.