But even if we confine our attention to products and services generally marketable, and to bargains thoroughly understood on both sides, there are still serious difficulties in the way of identifying the notions of ‘free’ and ‘fair’ exchange. Thus, where an individual, or combination of individuals, has the monopoly of a certain kind of services, the market-price of the aggregate of such services can under certain conditions be increased by diminishing their total amount; but it would seem absurd to say that the social Desert of those rendering the services is thereby increased, and a plain man has grave doubts whether the price thus attained is fair. Still less is it thought fair to take advantage of the transient monopoly produced by emergency: thus, if I saw Crœsus drowning and no one near, it would not be held fair in me to refuse to save him except at the price of half his wealth. But if so, can it be fair for any class of persons to gain competitively by the unfavourable economic situation of another class with which they deal? And if we admit that it would be unfair, where are we to draw the line? For any increase of the numbers of a class renders its situation for bargaining less favourable: since the market price of different services depends partly upon the ease or difficulty of procuring them--as Political Economists say, ‘on the relation between the supply of services and the demand for them’--and it does not seem that any individual’s social Desert can properly be lessened merely by the increased number or willingness of others rendering the same services. Nor, indeed, does it seem that it can be decreased by his own willingness, for it is strange to reward a man less because he is zealous and eager in the performance of his function; yet in bargaining the less willing always has the advantage. And, finally, it hardly appears that the social worth of a man’s service is necessarily increased by the fact that his service is rendered to those who can pay lavishly; but his reward is certainly likely to be greater from this cause.