Sorry, I am not interested in faith based arguments. What actual, specific secular or temporal harm does contraception bring along? That is the question.
You all have been busy on this topic!
As an habitue of a Catholic site, I presume you appreciate the difficulty Catholics have drawing the faith/secular line that you are asking. We just don’t draw it the same way.
For example, because Catholics believe in a literal Kingdom of God, which is perfect, we tend to evaluate things in light of that ideal. We ask “If we do such and such here, how closely can we match the world to the Kingdom?”
A practical example would be the old Truce of God. No one ever thought wars would stop, just that the world might be more peaceful, closer to the ideal.
The ideal from the Catholic perspective is that every person would have one mate. Leave monks and nuns out of the equation for the moment. Each person would be devoted to the mate, and not compete with his or her neighbor for their mate. The purpose of pairing would be to support each other and help care for one’s neighbors as one’s self, as well as begetting children. No lust, no greed, no coveting, no theft. That’s the ideal.
With the ideal in mind (and this is a marked difference between Catholic and modern democratic thought, which as Afghanistan and the EU illustrate, operates in the absence of ideals), Catholics ask what is likely to advance its achievement.
Sexual discipline is required, because without it, people will become accustomed to demanding sexual gratification on their own terms. Sexual discipline is needed for the same reason that fiscal discipline is needed. The person must become conditioned to putting his or her needs on the exact same plane as one’s neighbor, for the good of the general peace. Without practice and application, people cannot achieve the ideal, any more than soldiers can achieve collective bravery in the absence of training.
Based on what you have written, this is the opposite end from which you begin your analysis. You start with a hypothetical “If I am in a dark room, totally alone, and I begin to think about Anita Ekberg, who is harmed?” I reply: you are retarding your development as a chaste person, capable of maintaining the required self control. You see no potential victims. I see a soldier who fails to muster for parade, because he does not foresee the battle.
I grant you that the Catholic ideal may preclude the exuberance one finds in certain “blue films” (if one believes in that kind of thing). However, the ideal also precludes the child prostitution industry and the sad Knox case from Italy, to be more prosaic and topical.
That is probably the clearest I can make the Catholic “secular” argument. Catholics, like communists, have long realized that the rich and powerful find the ideal unattractive. Anyone who remembers Jack and the Beanstalk knows that giants don’t think much of shorter folks.
