The writing of Fernando Pessoa reveals a mind shaken by intense inner suffering. In these poems he adopted four separate personae: Alberto Caeiro, Alvaro de Campos, Ricardo Reis and himself, using them to express 'great swarms of thought and feeling'. While each personae has its own poetic identity, together they convey a sense of ambivalence and consolidate a striving for completeness.

Dramatic, lyrical, Christian, pagan, old and modern, Pessoa's poets and poetry contribute to the 'mysterious importance of existence'.