Inspired by the success of Newtonian analytical mechanics and thermodynamics, in the 18th and 19th centuries life scientists made use of concepts of force and energy to understand vital phenomena. When applied to the specificity of living beings, however, the concepts underwent important changes. With the establishment of scientific psychology in the 19th, we observe a similar movement in the treatment of psychic phenomena, especially considering the physiological training of most pioneer psychologists. The group intends to investigate the intricacies of this history, having as background the continuities and ruptures between the tortuous path of constitution of biology as an autonomous discipline and the positive approach to psychological processes.

Within the context of “crisis” and fragmentation of science in the 19th century, energy conservation provided an over-arching natural law, unifying all the sciences. These concepts, we maintain, provided a unifying conceptual framework tying together disciplines such as psychology, sociology, human physiology, medical practices, and political economy to the natural sciences. This history, however, bears an antecedent in the constitution of the life sciences in the 18th century, when dynamic concepts have equally played a structuring role in the formation of the Sciences of Man – and, in particular, in the debate classically defined as between mechanism vs vitalism. In conceiving the human in dynamic and energetic terms, the concepts of force and energy were not simply transplanted but transformed. These concepts, we contend, were assimilated with other traditions, generating concepts adapted to local purposes and practices, while maintaining its function of common currency – whereby allowing the concepts to be circulated within widely different domains, thus fertilising the generation of various epistemic practices.