Kant's position on this point seems impregnable. "It is surprising," he says, "that men otherwise astute can think it possible to distinguish between higher and lower desires, according as the ideas which are connected with the feeling of pleasure have their origin in the senses or in the understanding; for when we inquire what are the determining grounds of desire, and place them in some expected pleasantness, it is of no consequence whence the _idea_ of this pleasing object is derived, but only how much it _pleases_.... The only thing that concerns one, in order to decide choice, is how great, how long continued, how easily obtained and how often repeated, this agreeableness is. For as to the man who wants money to spend, it is all the same whether the gold was dug out of the mountain or washed out of the sand, provided it is every-where accepted at the same value; so the man who cares only for the enjoyment of life does not ask whether the ideas are of the understanding or the senses, but only _how much_ and _how great pleasure_ they will give for the longest time." See also Bradley, Op. cit., pp. 105-110. When we ask how the differences in quality are established and how we translate this qualitative difference into moral difference, the surrender of pleasure as the standard becomes even more evident. We must know not only the fact of different qualities, but how to decide which is 'higher' than any other. We must bring the qualities before a tribunal of judgment which applies to them some standard of measurement. In themselves qualities may be different, but they are not higher and lower. What is the tribunal and what is the law of judgment? According to Mill the tribunal is the preference of those who are acquainted with both kinds of pleasure.