Why all the negativity?
July 20, 2018 § 4 Comments
The negative precepts of the natural law are universally valid. They oblige each and every individual, always and in every circumstance. It is a matter of prohibitions which forbid a given action semper et pro semper, without exception, because the choice of this kind of behaviour is in no case compatible with the goodness of the will of the acting person, with his vocation to life with God and to communion with his neighbour. It is prohibited — to everyone and in every case — to violate these precepts. – Veritatis Splendour
Abstractly speaking an authority can take either a “whitelist” approach to property exchanges (only approved transactions are endorsed and enforced) or a “blacklist” approach (transactions are presumptively endorsed and enforced, but exceptions apply).
As a practical matter though the latter is the only real possibility for actual finite human authorities. Any attempt at the former proposes to actualize a potential infinite, and thus in practice would become a perverse and sociopathic version of the latter.
So blacklists it is. There is good reason why categorical commandments take the form “thou shalt not.”
(Originally a comment here).