From the Catholic Geek blog, they’re attempting to start a new series:
I’ve been meaning to start up an Ask a Catholic Geek series, and this question posed in our Facebook group was the perfect opportunity.
How do we explain, using moral theology, why it is licit to allow racists to use your credit card services? CAN we say it’s licit?
What level of material cooperation is licit? I think many people are deeply confused on this question.
~ Stephanie S.
Racism does not enter into it. What you are looking for is the following: When doesproviding a service to those who shall use the service to commit a sin mean I myself participate in that sin?
If you want St. Thomas Aquinas’ take on the subject, you don’t have to look any farther than Q. 169, on modesty. It’s one of my favorites to bring up, for two reasons. One, it has an inherent and very casual defense of the manufacture of weaponry (so casual that it’s obvious that St. Thomas didn’t even consider anyone might object to it, and he only brings it up to prove a point about modesty), and two, because I get a kick out of telling people that St. Thomas has a section on sexy lingerie.
Go read their argument!