326 PROFESSOR WHEWELL, ON CAUSE AND EFFECT. 



at any instant by the action of the force, is the instantaneous effect simul- 

 taneous with the cause. 



It may be objected, that this solution does not appear immediately 

 to apply : for the motion of a clock is not uniform during any portion 

 of the time. The parts move by intervals of varied motion and of rest ; 

 or by oscillations backwards and forwards; and the succession of forces 

 which acts during any oscillation, or any cycle of motion, is repeated 

 during the succeeding oscillation or cycle, and so on indefinitely ; and if 

 an alteration be made in the parts, it is not a change once for all, but 

 recurs in its operation in every cycle of the motion. 



But it will be found that this circumstance does not prevent the same 

 explanation from being still applicable with a slight modification. In- 

 stead of uniform motion in the intervals of causation, we shall have to 

 speak of steady going: and instead of considering all the forces which 

 affect the motion as causes of change of uniform motion, we shall have 

 to speak of changes in the parts of the mechanism as causes of change 

 of rate of going. With this modification, it will still be true, that 

 any instantaneous cause produces its instantaneous effect simultane- 

 ously, while the permanent effect is subsequent to the change which 

 is its cause. The steady going of the clock is assumed as a normal 

 condition, in which it measures the progress of time ; and in this assump- 

 tion, the notion of cause and effect is not brought into view. But a 

 steady rate thus denoting the mean passage of time, a change in the 

 rate indicates a cause of change. The change of rate, as an instantaneous 

 transition from one rate to another, is simultaneous with the change 

 in the parts. But then the changed rate as a continued condition in 

 which, no new change supervening, the rate again measures the progress 

 of time, is subsequent to the change of parts, for it begins when that ends, 

 and continues when the progress of that has ceased. 



If, however, this be a satisfactory solution of the difficulty in the case 

 of mechanism, how shall we apply the same views to the other cases ? 

 Growth, the effect of food, is subsequent to the act of taking food ; 

 disorder, the effect of poison, is subsequent to the introduction of poison 

 into the system. Can we say that the animal would continue unchanged 



