Spinoza - Ethics 2, Preface, Definitions and Axioms HOME Intro. MT ST TEI Ethics TPT Corr. By body I mean a mode which expresses in a certain determinate manner the essence of God, in so far as he is considered as an extended thing. By idea , I mean the mental conception which is formed by the mind as a thinking thing. By an adequate idea , I mean an idea which, in so far as it is considered in itself, without relation to the object, has all the properties or intrinsic marks of a true idea.
Duration is the indefinite continuance of existing.
I say indefinite, because it cannot be determined through the existence itself of the existing thing, or by its efficient cause, which necessarily gives the existence of the thing, but does not take it away. Reality and perfection I use as synonymous terms. The essence of man does not involve necessary existence, that is, it may, in the order of nature, come to pass that this or that man does or does not exist. Modes of thinking , such as love , desire , or any other of the passions , do not take place, unless there be in the same individual an idea of the thing loved , desired, etc. But the idea can exist without the presence of any other mode of thinking .