nowledge, and foresight of probable necessity; but the
greater part of such gain is unjust; and unjust in this most fatal way,
that it depends, first, on keeping the exchangers ignorant of the
exchange value of the articles; and, secondly, on taking advantage of
the buyer's need and the seller's poverty. It is, therefore, one of the
essential, and quite the most fatal, forms of usury; for usury means
merely taking an exorbitant[47] sum for the use of anything; and it is
no matter whether the exorbitance is on loan or exchange, on rent or on
price--the essence of the usury being that it is obtained by advantage
of opportunity or necessity, and not as due reward for labour. All the
great thinkers, therefore, have held it to be unnatural and impious, in
so far as it feeds on the distress of others, or their folly.[48]
Nevertheless, attempts to repress it by law must for ever be
ineffective; though Plato, Bacon, and the First Napoleon--all three of
them men who knew somewhat more of humanity than the "British merchant"
usually does--tried their hands at it, and have left some (probably)
good moderative forms of law, which we will examine in their place. But
the only final check upon it must be radical purifying of the national
character, for being, as Bacon calls it, "concessum propter duritiem
cordis," it is to be done away with by touching the heart only; not,
however, without medicinal law--as in the case of the other permission,
"propter duritiem." But in this more than in anything (though much in
all, and though in this he would not himself allow of their application,
for his own laws against usury are sharp enough), Plato's words in the
fourth book of the Polity are true, that neither drugs, nor charms, nor
burnings, will touch a deep-lying political sore, any more than a deep
bodily one; but only right and utter change of constitution: and that
"they do but lose their labour who think that by any tricks of law they
can get the better of these mischiefs of commerce, and see not that they
hew at a Hydra."

99. And indeed this Hydra seems so unslayable, and sin sticks so fast
between the joinings of the stones of buying and selling, that "to
trade" in things, or literally "cross-give" them, has warped itself, by
the instinct of nations, into their worst word for fraud; for, because
in trade there cannot but be trust, and it seems also that there cannot
but also be injury in answer to it, what is merely fraud between enem