90 INDUCTION. 



though during five thousand years they have not 

 amounted to a perceptible quantity, will in one day 

 become overwhelming. Since this cause has not been 

 recognised during such an interval of time, by 

 observers stationed on our earth, it must, if it exist, 

 be either some agent whose effects develope them- 

 selves gradually and very slowly, or one which existed 

 in regions beyond our observation, and is now on the 

 point of arriving in our part of the universe. Now 

 all causes which we have experience of, act according 

 to laws incompatible with the supposition that their 

 effects, after accumulating so slowly as to be imper- 

 ceptible for five thousand years, should start into 

 immensity in a single day. No mathematical law of 

 proportion between an effect and the quantity or rela- 

 tions of its cause, could produce such contradictory 

 results. The sudden developement of an effect, of 

 which there was no previous trace, always arises from 

 the coming together of several distinct causes, not 

 previously conjoined ; but if such sudden conjunction 

 is destined to take place, the causes, or their causes, 

 must have existed during the entire five thousand 

 years; and their not having once come together during 

 that period, shows how rare that particular combina- 

 tion is. We have, therefore, the warrant of a rigid 

 induction for considering it probable, in a degree 

 undistinguishable from certainty, that the known 

 conditions requisite for the sun's rising will exist 

 to-morrow. 



3. But this extension of derivative laws, not 

 causative, beyond the limits of observation, can only be 

 to adjacent cases. If instead of to-morrow we had 

 said this day twenty thousand years, the inductions 

 would have been anything but conclusive. That a 



