MIND AND SOUL The monads that correspond to a human body in the Leibnizian system are like cells in having an individual life-history, but unlike cells in being immaterial and immortal We have come a long way from our Cartesian starting point For Descartes, human minds were the only souls in the created universe; all else was lifeless machinery For Leibniz, the smallest part of the smallest bug is ensouled—and it has not only one, but myriad souls We have indeed gone further than Aristotle, for whom only living things had souls Now there are souls galore behind every stock and stone What, in this pullulating maelstrom of monads, makes the human mind unique? For Leibniz, the diVerence between living and non-living bodies is this Organic bodies are not mere aggregates of monads: they have a single dominant monad which gives them an individual substantial unity The dominant monad in a human being is the human soul All monads have perception and appetite, but the dominant monad in a human being has a more vivid mental life and a more imperious appetition It has not just perception, but ‘apperception’, which is self-consciouness, reXexive knowledge of the internal states that constitute perception Whereas we know of the existence of other monads only by philosophical reasoning, we are aware of our own substantiality through this self-consciousness ‘We have a clear but not a distinct idea of substance,’ Leibniz wrote in a letter, ‘which comes, in my opinion, from the fact that we have the internal feeling of it in ourselves’ (G III.247) The good of the soul is the goal, or Wnal cause, not just of its own activity, but also of all the other monads that it dominates The soul does not, however, exert any eYcient causality on any of the other monads, nor any of them on any other: the good is achieved in virtue of the harmony pre-established by God in the body and in its environment and throughout the universe Once again, Leibniz’s rehabilitation of Aristotle goes further than Aristotle himself Final causes were just one of Aristotle’s quartet of causes; Descartes had expelled them from science but they are now readmitted and enthroned as the only Wnite causes operative in biology In all of this, is any room left for free will? In theory, Leibniz defends a full libertarian doctrine: Absolutely speaking, our will, considered as contrasted with necessity, is in a state of indiVerence, and it has the power to otherwise or to suspend its action altogether, the one and the other alternative being and remaining possible (D, 30) 234