lotka: objective standard of value 451 



some circumstance peculiar to its case, form an exception, and 

 have a large error e. Now this will not seriously affect our argu- 

 ment, provided only that such peculiar exception does not occur 

 in the case of the one commodity which enters as a standard into 

 our system — namely labor. Now it is quite possible that labor 

 does constitute such an exceptional case: the sense of fatigue is 

 given us to warn us of possible harm which may be incurred if 

 labor is persisted in after it has become irksome beyond a certain 

 point. It is well known that in many other instances nature pro- 

 vides for emergencies by allowing a large "factor of safety," and 

 we may well expect that such a factor should enter as a correction 

 in equation (27) : The individual will not wait until that equation 

 is satisfied, but will cease to labor as soon as 



Sxf^=-1 (30) 



where iS is a factor of safety, and, as such, greater than unity. 



The neglect of this factor of safety in our estimate of ^~^ above 



would produce an error in the same direction as the neglect of the 

 effect of monopolies and capital. The corrections to be applied 

 would therefore all work in the same direction and tend to bring 



the value of -j: thus obtained into seemingly better harmony 



with the expectations which we are naturally led to entertain on 

 the basis of observation. 



Lastly, we have made the assumption that wi = coi (mi), i.e., 

 the marginal ophelimity of conmiodity Ai depends only on the 

 quantity of Ai consumed per unit of time, and is independent of 

 the rate of consumption of other commodities. This assumption 

 is not strictly true in any case, and may be quite far from the 

 truth in some cases. This assumption does not, however, mate- 

 rially affect our arguments and conclusions, and was made here 

 only for the sake of simplicity. The consideration of the more 

 general case, in which this assumption is discarded, is passed over 

 here, and will be found at the end of this paper. 



