52 INTRODUCTION 



inferior Monads. Thus both animals and men have 

 unconscious as well as conscious perceptions, for ex- 

 ample, when they fall into a faint or have a profound 

 and dreamless sleep 1 . In such a case they are not 

 entirely destitute of perceptions, for the Monad is inde- 

 structible (being indivisible) and it cannot exist without 

 perception of some kind. The changes of the Monad 

 are entirely from within, so that when the man or 

 animal awakes out of a sleep or trance his conscious 

 perceptions must have unfolded themselves out of imme- 

 diately preceding perceptions of an unconscious kind 2 . 

 Again, men share with the animals both sense-perception 

 and the empirical sequence of memory and imagination, 

 which bears a resemblance to the concatenation of rational 

 thought, but may be sufficiently distinguished from it 3 . 

 Indeed, in most of our actions and beliefs we are empi- 

 rics, as for instance when we expect the dawn, not 

 because we know the cause of it, but because it has 

 happened regularly in the past 4 . 



Self-consciousness in the Philosophy of Leibniz and in 

 that of Descartes. 



The significance of this may be brought out by a 

 reference to the position of Descartes, which Leibniz 

 probably had in view. According to Descartes, the 

 rational soul is the mind and its reality comes only from 

 its conscious certainty of itself. Thus without self-con- 

 sciousness there is no mind or soul. Animals have no 

 self-consciousness and therefore they have no souls they 

 are mere machines. But animals have sensations and 

 impulses, and consequently sensation and impulse are 

 not functions of self-consciousness, acts of the soul, but 

 are purely physical and mechanical processes, whether 

 they occur in man or in the lower animals. It is in 



1 Monadology, 20. 2 Ibid. 22 and 23. 



8 Ibid. 26 sqq. Cf. Nouveaux Essais, bk. ii. ch. n (E. 237 ; 

 G. v. 129), and Eraser's ed. of Locke's Essay, vol. i. p. 208. 

 * Monadology, 28. 



