 Fechner’s first exposition of panpsychism is his Nanna oder über das Seelenleben der Pflanzen, which he first published in 1848. Nanna took the first step toward panpsychism by arguing that plants are conscious beings, having a life of feeling and volition. In his Zend-Avesta, which first appeared in 1851, Fechner took his panpsychism a giant step further by contending that planets, and indeed the cosmos as a whole, are also psychic or mental. Fechner defended and elaborated his panpsychism in two works of the early 1860s: Ueber die Seelenfrage (1861) and Die Drei Motive and Gründe des Glaubens (1863). His final exposition of his doctrine appears in his Die Tagesansicht gegenüber der Nachtansicht (1879).