EXTENSION OF LAWS TO ADJACENT CASES. 91 



cause which, in opposition to very powerful causes, 

 produced no perceptible effect during five thousand 

 years, should produce a very considerable one by the 

 end of twenty thousand, has nothing in it which is 

 not in conformity with our experience of causes. We 

 know many agents, the effect of which in a short 

 period does not amount to a perceptible quantity, but 

 by accumulating for a much longer period becomes 

 considerable. Besides, looking at the immense multi- 

 tude of the heavenly bodies, their vast distances, 

 and the rapidity of the motion of such of them as are 

 known to move, it is a supposition not at all con- 

 tradictory to experience that some body may be in 

 motion towards us, or we towards it, within the limits 

 of whose influence we have not come during five 

 thousand years, but which in twenty thousand more 

 may be producing effects upon us of the most extra- 

 ordinary kind. Or the fact which is capable of pre- 

 venting sunrise may be, not the cumulative effect of 

 one cause, but some new combination of causes ; 

 and the chances favourable to that combination, 

 though they have not produced it once in five thou- 

 sand years, may produce it once in twenty thousand. 

 So that the inductions which authorize us to expect 

 future events, grow weaker and weaker the further 

 we look into the future, and at length become inap- 

 preciable. 



We have considered the probabilities of the sun's 

 rising to-rnorrow, as derived from the real laws, that 

 is, from the laws of the causes on which that unifor- 

 mity is dependent. Let us now consider how the 

 matter would have stood if the uniformity had been 

 known only as an empirical law ; if we had not been 

 aware that the sun's light, and the earth's rotation (or 

 the sun's motion), were the causes on which the 



