When all is said and done, which model of the mind–body relationship emerges from an examination of Spinoza's conception of the affects? Exploring how the power of acting operates in the affects has made it possible to show how the psychophysical union varies, and reconciles a similarity of order and principle with the mind and body's autonomy of expression. The first point therefore is to stop searching for any interaction, influence or reciprocal causality between the mind and the body, and to think of them only in terms of correspondence and correlation.

From this perspective, the American neurologist Antonio Damasio was right in maintaining that in Spinoza ‘in a strict sense, the mind did not cause the body and the body did not cause the mind’. However, Damasio is not always worthy of his model and sometimes lacks rigour, since he continues to talk about the mind arising from the body and going from the neural to the mental level, which Spinoza could not have accepted. It is true that it is naturally very difficult to do without the categories of cause and reciprocal action when conceptualising the mind–body relationship, and it is tempting to bring them back in another guise. In this respect, meditating on Spinoza's model is an excellent safeguard against attempts to establish a relationship on the basis of an interaction or influence model, which would always retain its ‘occult’ qualities.

Although Spinoza's model excludes interaction in favour of correlation, it cannot be reduced for all that to an interplay of parallels between mind and body that express the same thing under two different attributes. This is the second point to make from studying the affects. Spinoza's model of the psychophysical union is not based on parallelism but on equivalence. This equivalence is not uniformity, since it cannot be reduced to echoing the same thing and to mechanical repetition.