By the highest good, I mean the ultimate purpose toward which all human thought and action, creativity and aspiration should aim, not only for the individual but also in relation to which all people should unite. With the determination of this highest good, the highest moral principle is simultaneously defined. This highest good and the actions directed toward it have been sought to be expressed in various ways. It is a philosophically highly stimulating thought experiment that the physicist and philosopher Gustav Theodor Fechner (1801-1887) engages in here. Fechner's description encourages everyone to reflect on their own life design in an easily understandable manner. This book is an unaltered reprint of the original edition from 1846.