364 NEW ESSAYS 



inner principles which are called innate. It is true we 

 must not imagine that we can read these eternal laws of 

 reason in the soul as in an open book 32 , as the edict 

 of the praetor may be read on his album 3S without trouble 

 or investigation ; but it is enough that we can discover 

 these laws in ourselves by means of attention, for which 

 opportunities are furnished by the senses ; and the 

 success of experiments serves also as a confirmation of 

 reason, somewhat as in arithmetic l proofs ' are useful in 

 helping us to avoid errors of calculation when the process 

 is a long one. In this also lies the difference between 

 human knowledge and that of the lower animals. The 

 lower animals are purely empirical and direct them- 

 selves by particular instances alone ; for, so far as we can 

 judge, they never succeed in forming necessary proposi- 

 tions ; while men, on the other hand, have the capacity 

 for demonstrative science. It is also on this account that 

 the power of making concatenations [of ideas] which the 

 lower animals possess is something inferior to the reason 

 which is in men 34 . The concatenations [of ideas] made by 

 the lower animals are simply like those of mere empirics, 

 who maintain that what has sometimes happened will 

 happen again in a case which resembles the former in 

 characteristics which strike them, although 85 they are 

 incapable of judging whether or not the same reasons 

 hold good in both cases. That is why it is so simple 

 a matter for men to entrap animals, and so easy for 

 mere empirics to make mistakes. From this making of 

 mistakes even persons who have become skilful through 

 age and experience are not exempt, when they trust too 

 much to their past experience, as some have done in civil 

 and military affairs ; because enough consideration is 

 not given to the fact that the world changes and that 



32 a livre ouvert, lit. = ad aperturam libri. 



33 i. e. the tablets with 'notices/ posted up in a public place, so 

 that he who runs may read. 



34 Cf. Monadology, 26-29. S5 E. adds ' for all that.' 



