Aristotle’s philosophy having been brought to the West, it was very attractive to the subtle minds who in times of ignorance are the leading lights. The scholastics became infatuated with it, and took their doctrine on lending at interest from that philosopher  : they conflated it with usury and condemned it. In that way commerce, which was the profession only of the baseborn, became in addition the profession of the dishonest : for every time we forbid something naturally permissible or necessary, all we do is turn those who profess it into dishonest men.
Commerce passed to a nation then covered with infamy, and soon was no longer distinguished from the most horrendous usuries, monopolies, the levying of subsidies, and all dishonest means of acquiring money.
The Jews, enriched by their exactions, were pillaged with the same tyranny by princes, which gave the people consolation but not relief. 
What happened in England will give an idea of what was done in other countries. King John had the Jews imprisoned to get their property, and there were few of them who did not have at least an eye put out  : that is how the king conducted his chamber of justice. One of them, who had seven teeth pulled, one every day, yielded ten thousand silver marks on the eighth. Henry III extracted from Aaron, a York Jew, fourteen thousand silver marks, plus ten thousand for the queen. In those times they did violently what is done today in Poland with some restraint. The kings, being unable to rummage in the purse of their subjects because of their privileges, would put to the torture Jews, who were not regarded as citizens.
Finally, a custom was introduced which confiscated all the assets of Jews who would embraced Christianity. This passing strange custom is known to us only from the law that abrogates it.  Utterly vain reasons have been given for it : it has been said that they wanted to test them, and to make sure nothing should remain of their enslavement to the devil. But it is obvious that this confiscation was a sort of right of amortization, for the prince or for the lords, of taxes they levied on the Jews,  and of which they were deprived when the Jews embraced Christianity. In those times men were regarded as lands ; and I shall note in passing how that nation was toyed with century after century. Their assets were confiscated when they wanted to be Christians, and soon afterwards they were burned when they did not.
Nevertheless, commerce arose from the bosom of harassment and despair. The Jews, proscribed in turn by every country, found the means of saving their effects. In that way they made their retreats forever fixed : for a prince who would like to be rid of them would not for that be in a mood to get rid of their money.
They invented the letter of exchange  ; and by this means commerce was able to avoid violence, and maintain itself everywhere, the richest trader having only invisible assets that could be sent everywhere and left no trace anywhere.
The theologians were obliged to narrow their principles, and the commerce which had been violently linked to bad faith returned, so to speak, into the bosom of probity.
Thus we owe to the speculations of the scholastics all the misfortunes that have accompanied the destruction of commerce, and to the avarice of princes the establishment of something that puts it more or less beyond their power.
Since that time, princes have had to govern themselves more prudently than they themselves would have thought ; for it has turned out that great authoritative interventions have proven so clumsy that it is a recognized experience that only the benignancy of the government can bring prosperity.
We have begun to get over Machiavellianism, and will continue every day to do so. There must be more moderation in the councils. What used to be called coups d’État would be today, independently of the horror, merely imprudent acts.
And it is fortunate for men to be in a situation where, while their passions inspire them to be wicked, it is nevertheless in their interest not to be.