In this chapter I would simply like to present some remarks on the reasons that justify Proposition 39 of Part V of the Ethics: ‘He who has a Body capable of a great many things has a Mind whose greater part is eternal.’ In order to do this, given that the eternity of our mind has a relation to intellectual knowledge, we must first of all try to specify what exactly is the correlate of our adequate ideas: what happens in the body when the mind understands? After that, we will be better able to understand what Spinoza tells us about the relations between the body and eternal life.

What is the corporeal correlate of our adequate ideas? We know, of course, what corresponds to universal common notions and proper common notions: for the former, it is the properties that are common to all bodies and that are equally in the whole and in the parts of each; and, for the latter, the properties that are common to our bodies and to certain external bodies by which they are usually affected, and that are equally in the whole and in the parts of each of these external bodies. We also know what the correlate of the true idea of God is: it is God itself, considered under the attribute of Extension, which is present in each and every one of our body’s affections. But what is the correlate of the deductions that we undertake based on common notions or the idea of God? On this point, we can look to Proposition 10 of Part V, to which the demonstration of Proposition 39 refers: ‘So long as we are not torn by affects contrary to our nature, we have the power of ordering and connecting the affections of the Body according to the power of the intellect.’ And the demonstration explains: so long as we are not torn by affects contrary to our nature, our mind is not prevented from understanding; thus it understands, in this way organising its adequate ideas according to the order of deduction; and consequently, in our bodies, affections are organised in the same order.