This was especially confounded by progressive scholastics’ use of a proposed distinction between putatively ‘productive’ interest bearing mutuum loans to businessmen (explicitly condemned in Vix Pervenit, see Question 25) and putatively ‘unproductive’ mutuaa
It was also the case that usury was frequently misunderstood, and many contracts which were not usury were condemned as such by overzealous but financially ignorant people. An analogous case in the context of the sexual revolution would be the ‘rigorists’ who condemn NFP as a form of contraception, and their ‘laxist’ counterparts who make the same claim but conclude from it that therefore contraception is morally licit. The spectacle of a penitent, innocent of usury, hounded and denied absolution by an overzealous confessor who doesn’t properly understand the subject, may be a risible fiction now; but that was not always the case.
The argument over ‘productive’ vs ‘unproductive’ mutuum loans snookered the traditionalists by framing the debate in question begging terms, obscuring the essential distinction (the distinction, unlike ‘productive’/’non-productive’, actually found in Magisterial documents on usury such as Cum Onus and Regimini Universalis) between mutuum (full recourse) loans and legitimate non recourse (societas) business investment.
Aquinas and the Popes who addressed the issue in bulls and encyclicals may have understood the difference between non recourse (societas) investment and full recourse (mutuum) loans, but many priests at the parish level did not
An especially pernicious false-flag argumentative tactic of present day usury apologists is to take the ‘rigorist’ approach as a way of discrediting the dple that the traditional understanding of usury would disallow all census-type contracts involving regular payments of principal and interest (e.g. corporate bonds), not just those census contracts with claims that terminate in persons as opposed to or in addition to actual property. (See question 31). This ‘false flag’ approach is aided and abetted by useful idiots on the traditionalist or reactionary side who cheer on their ‘rigorist’ arguments.
Usury would of course be intrinsically immoral even if that did, counterfactually, make industry and commerce impossible or if it were unhealthy in some sense for industry and commerce – just as contraception would remain intrinsically immoral even if the lack of it led inexorably to overpopulation and misery. Like moral doctrine on contraception it merely prohibits actions which are objectively harmful both to the parties involved and to the common good – even though they do involve a short term ‘payoff’ of sorts, which is why they are tempting. This is why the arguments in favor of laxity on contraception and usury tend to mirror and cross-reference each other (myriad examples can be found simply by Googling various combinations of the terms “usury”, “Catholic”, and “contraception”).
Apologists for contraception have learned the playbook from the apologists for usury: give lip service to the doctrine as an important decorative piece of theology up in the sky; “pastorally” defang it so that in practice it can be ignored on the ground; continue to “dialogue” until the right “pastoral” result is achieved; paint any opposition into a corner as unmerciful, impractical, and disconnected from reality; and assert that this “pastoral” result was a development of doctrine, ignoring the dog that doesn’t bark – the nonexistent teaching documents from the Magisterium representing an actual dent”. Do the latter enough times over a long enough period so that everyone starts to accept it as a given, including much of the clergy. Continue to point out various “defects” in the “simplistic” understanding articulated in Magisterial documents, and be sure to reiterate regularly that they are not infallible. Oh, and point out the sexual peccadillos, I mean economic practices, in clergy and the Vatican: because if the Vatican does something in its secular operations or practices that constitutes an infallible proclamation that the practices cannot be immoral, as long as they are the things we want to not be immoral, and anyway it isn’t really immoral but if the Church actually means what it says doctrinally in those defective non-infallible documents then it is being hypocritical. Shout down any alternative description of the situation on that front as excuse-making. Once all that is achieved all remaining objections must be marginalized and ridiculed. Pat the old celibate economically illiterate men in the Holy See on the head for their prior silly immaturity, congratulate the laity for its wisdom about the “facts of life” and the sensus fidelium, and move on.