Human Sexuality: Unitive And Procreative

[icelandic_iceskater]

How do you explain this without bringing God into the picture?

Can you at all?

[Laudate_Dominum]

One approach would be to present your case from a personalistic philosophical perspective. If you can convince your atheist friend to accept the personalistic norm in both its positive and negative formulations I believe it would be fairly easy to meaningfully elucidate the ends of human sexuality from within the confines of naturalistic and humanistic categories.
A great resource in this regard would be Wojtyla's book [i]Love and Responsibility[/i]. If you don't have time to read the whole thing there is a good summary of this book here: [url="http://www.christendom-awake.org/pages/may/summaryofl&r.htm"]http://www.christendom-awake.org/pages/may...ryofl&r.htm[/url]

If you are interested in further research I would recommend the writings of Dietrich von Hildebrand who happens to be one of my favorites, for example:

[i]Marriage: The Mystery of Faithful Love[/i]
[i]In Defense of Purity[/i]
[i]Fundamental Moral Attitudes[/i]
[i]Ethics[/i]
[i]Man and Woman: Love & the Meaning of Intimacy[/i]
[i]Love, Marriage, and the Catholic Conscience[/i]
[i]Das Wesen der Liebe[/i] (English translation forthcoming)

There are also many contemporary authors worth checking out and I might indicate Prof. William E. May (from the link above) as one possible resource. One book that comes to mind is [i]The Teaching of Humanae Vitae: A Defense[/i], by William May, John Ford, Germain Grisez, Joseph Boyle, and John Finnis.

[Laudate_Dominum]

I should note that [i]Das Wesen der Liebe[/i] coupled with [i]Ethics[/i] would provide a very solid foundation in the philosophical approach of von Hildebrand (mastering von Hildebrand’s ethical philosophy would equip you with a formidable arsenal in debating Christian ethics with persons of any persuasion). I know the fellows who have been working on the English translation of [i]Das Wesen der Liebe[/i] and based on our last correspondence on this topic (about two years ago) it may be complete by now. I am actually curious myself so I will either inquire via email or stop one of them the next time I see them at Mass and I will post any updates on this translation project here.

[Laudate_Dominum]

Ok, it should be available on June 15, 2008.

You can pre-order it here: [url="http://www.amazon.com/Nature-Love-Dietrich-von-Hildebrand/dp/1587315602/ref=pd_bbs_2?ie=UTF8&s=books&qid=1206827728&sr=8-2"]The Nature of Love[/url] ([i]Das Wesen der Liebe[/i])

[Theoketos]

To sum up the Argument that L_D mentions:

It is wrong to use another person, because persons are ends in themselves and never means.

If sex is just for "union", and not for procreation as well, then one person is using for the other for the sake of pleasure. This violates friendship and dignity and therefore is immoral.