That this perfectly natural conception to us has become so unnatural, must be laid to the charge of our habits of thought, trained one-sidedly as we have been, along the lines of mechanical views. Where something happens, we look for some impulse from without; but we ought never to forget that science does not give the actual world at all, but only a re-actual world; in which world, to be sure, impulses must be given if anything is to happen at all. The mechanical world-theory is simply a “reading” of the play of world-events in order to give computation and determination in advance; never under any circumstances does it furnish an insight into actuality itself. Actuality is action out of itself; it is the self-active. And all the insoluble problems in which science loses her way when she seeks to carry the mechanical comprehension of the play of world-events from the reversible processes where it is possible and legitimate, over to the non-reversible processes, all in the last analysis amount to this, that one is trying to demonstrate something--_i.e._ the biological process--from external preconditions, which along such lines can never be demonstrated, not because in itself incapable of demonstration, but because it is demonstrating itself through itself. This the genuine thinker must absolutely hold to. Actuality is action itself, not something that first must be acted upon. Everything re-actual is thinkable only as the sequel of a push requires a push for its explanation. Everything that is actual burns. After this, what takes place in the _I_-process becomes comprehensible. Here the passing over from potential to living energy has its counterpart in the _volitional movements_. At every moment of its existence the _I_-process represents a specific value in potential energy which there where the external world enters with its “liberating” provocations, ever and again passes over into living energy as volitional movement. Every discharge in the form of a volitional movement is a charging afresh with potential energy. It is a self-sustaining proceeding in the fullest sense of the words. The volitional movements are the ever repeated new foothold which the _I_ fashions for itself, the ever repeated “sustenance” wherewith it provides itself afresh.