  Spinoza’s thesis (IIIp7) that the essence of any finite mode, including any human mind (IIIp9), is a striving (conatus) to persevere in being is an attempt to give an account of nature under which human beings with their apparent peculiarities are natural. Spinoza argues that all finite modes strive to persevere in being (IIIp6), and he uses an analysis of human striving to explain the conscious experience of desire, human freedom, and good and evil in terms that might apply to any finite modes. Desire, as Spinoza understands it, just is striving together with consciousness of striving (IIIp9s; the human experience of desire is discussed in more detail in Section 2.1). An action of a human mind cannot be free, for Spinoza, in the sense of being determined by a faculty of will that is itself undetermined (IIp48; see also letter 58, to Schuller). There is human freedom for Spinoza, however, in the sense of freedom from external interference: I am free in producing some effect (that is, in doing something) to the extent that the effect follows from my essence, or, in other words, to the extent that it is the effect of my striving. (For discussions of action and human freedom, see IIId2 and V Preface.) ‘Good’ and ‘evil’ are labels that describe natural properties in the sense that they describe changes that might occur in any particular things at all (although we reserve the labels for these changes when they occur in human beings).  Although scholars debate the precise meaning of these identifications, an increase in the power with which a mind strives is good, for Spinoza, and a decrease evil (see IIIp11s, IIIp39s and IV Preface).  Because the striving thesis thus makes central contributions to Spinoza’s accounts of consciousness, of human freedom and of good and evil, it is of great importance to Spinoza’s psychology and ethics. One might raise questions about the validity of Spinoza’s argument to the doctrine, about its plausibility as an account of the nature of particular objects, or about its plausibility as an account of human nature. The subsections which follow address these issues in turn.