[199] By this Schopenhauer means the distinction between _the will_ in its widest sense, regarded as the fundamental essence of all that happens,--even where there is no choice, even where it is _unconscious_,--and _conscious will_, implying deliberation and choice, commonly called _free-will_. We must however carefully guard against confounding this _relative_ free-will, with _absolute_ free-will (_liberum arbitrium indifferentiæ_), which Schopenhauer declares to be inadmissible. The sense in which I have used the expression '_free-will_' throughout this treatise, is that of _relative_ freedom, _i.e._ power to choose between different motives, free of all outward restraint (_Willkühr_). (Tr.)

[200] I have shown the difference between _cause_ in its narrowest sense, _stimulus_, and _motive_, at length in my "Grund-probleme der Ethik" p. 29 _et seq._

On the Fourfold Root of the Principle of Sufficient Reason and On the Will in Nature: Two Essays (revised edition) — Part 138

As soon therefore as we have got so far as to distinguish _will_ [_Wille_] from _free-will_ [_Willkühr_], and to consider the latter as a particular kind or particular phenomenon of the former, we shall find no difficulty in recognising the will, even in unconscious processes. Thus the assertion, that all bodily movements, even those which are purely vegetative and organic, proceed from _the will_, by no means implies that they are voluntary. For that would mean that they were occasioned by motives; but motives are representations, and their seat is the brain: only those parts of our body which communicate with the brain by means of the nerves, can be put in movement by the brain, consequently by motives, and this movement alone is what is called voluntary. The movement of the inner economy of the organism, on the contrary, is directed, as in plant-life, by _stimuli_; only as, on the one hand, the complex nature of the animal organism necessitated an outer sensorium for the apprehension of the outer world and the will's reaction on that outer world, so, on the other hand, did it necessitate a _cerebrum abdominale_, the sympathetic nervous system, in order to direct the will's reaction upon inner stimuli likewise. We may compare the former to a Home Ministry, the latter to a Foreign Office; but the will remains the omnipresent Autocrat.

On the Fourfold Root of the Principle of Sufficient Reason and On the Will in Nature: Two Essays (revised edition) — Part 138