Some principles need to be employed. The principles of double effect, remote or proximate cooperation, and material or formal cooperation.
This set of criteria states that an action having foreseen harmful effects practically inseparable from the good effect is justifiable if upon satisfaction of the following:
* the nature of the act is itself good, or at least morally neutral;
* the agent intends the good effect and not the bad either as a means to the good or as an end itself;
* the good effect outweighs the bad effect in circuмstances sufficiently grave to justify causing the bad effect and the agent exercises due diligence to minimize the harm.
Now the good effect (temporarily feeding your family) does NOT outweigh the bad effect (MORTAL SIN, INFINITE MALICE AGAINST GOD).
But the person who buys the condoms was already advertised to, taught they were good by teachers, etc., decided he wanted them, and went to the store to buy them. Wal-mart corporate decided to carry them at all their stores.
When looked at this way, HOW MUCH contribution is the stockboy contributing to Joe Public committing the sin of contraception?
And it's not infinite malice against God, it's "who knows how much" malice against an infinite God. You're confusing why the sin is infinite.
The small contribution by the truck driver carrying a couple boxes of them to the store (less than 1% of his cargo), the janitor, the stockboy, the cashier is miniscule and the justification of "I have to feed my family" is CERTAINLY enough to outweigh any evil done.
You haven't shown me any evidence that my assertion is wrong.
You haven't been Catholic nearly as long as I have, and I bet you haven't read as much as I have either. I've been traditional Catholic my whole life, which is over 3 decades long. I've read hundreds of books, and I attended a traditional Catholic seminary for 3 1/3 years. I think my Sensus Catholicus is in better working order than yours.
Let the readers be the judge. They can follow whose advice they think more prudent.
Matthew