In his 1889 dissertation "Essai sur les données immédiates de la conscience" (first German edition 1911), Bergson attempts to place the issue of freedom and determinism on a fundamentally new foundation. In this early work, he already lays the groundwork for the complex web of concepts he develops in his later writings. The main thesis is as follows: The problem of freedom arises from a misunderstanding of the concept of time, stemming from the conflation of the temporal with the spatial. Bergson demonstrates this in three steps, beginning with an analysis of states of consciousness in the first chapter. Starting from the distinction between stimulus and sensation, and engaging with the physical and psychological theories of his time, Bergson shows that while the stimulus can be quantitatively measured, the sensation cannot.