Wherefore these decisions of the mind arise in the mind by the same necessity, as the ideas of things actually existing.
Therefore those who believe, that they speak or keep silence or act in any way from the free decision of their mind, do but dream with their eyes open.
PROP.III.

The activities of the mind arise solely from adequate ideas; the passive states of the mind depend solely on inadequate ideas.
Proof .-- The first element, which constitutes the essence of the mind, is nothing else but the idea of the actually existent body (II.xi.and xiii.), which (II.

xv.) is compounded of many other ideas, whereof some are adequate and some inadequate (II.
xxix.Coroll., II.xxxviii.

Coroll.).

Whatsoever therefore follows from the nature of mind, and has mind for its proximate cause, through which it must be understood, must necessarily follow either from an adequate or from an inadequate idea.