Eventually I think we would see that “proper us” as immorality only applies to the special cases of penises, vaginas, and rectums and this general principle is revealed as a specific prejudice against homosexual acts.
I think this is a mistake about natural law. On the other hand, it may not be such a mistake about certain members of this forum or of people in the world in general.
I think natural law, when dealing with homosexual acts or with contraceptive acts (both of which I have threads for now) is far less interesting or useful than natural law applied to other situations.
Natural law is at its most interesting, for me, when applied to the issue of private property, or government. This is because it’s most ambiguous in these regions, and so there’s a wide range of available opinion and study. The most difficult problems for natural law are in this regime, I think.
Natural law is at its most useful for me when applied to human pride, and the right end of the use of the human intellect, because this is where I sin most greatly, and so this is where I can grow most. Natural law has been a great boon for my moral development, and has (in part) made me a happier person, a more productive scientist, and generally an easier person to get along with.
I’m not at all convinced that it follows logically to say that X was designed for Y therefore to us it for Z is immoral. Using X for Z may indeed be immoral, but talk of Nature gets us nowhere in articulating what is wrong about it because of that Is-Ought gap.
I think it bridges the is-ought gap axiomatically (as do most ethical systems, if you think about it. It’s either an axiom or a loaded definition). That is that every action and group of actions committed by any indvidual tends toward a certain end, and that a will that wills a different end than the purposed end necessarily wills something evil (something that is not the proper good).
This exposes the two great weaknesses of natural law. It possesses one weakness common to all ethical systems I have studied, in that it necessarily relies on certain principles, the rejection of which ends the conversation. For example, if someone simply disagrees with the categorical imperative, or thinks that suffering has nothing to do with what is right, we might be skeptical of his or her dismissal, but the rational argument about deontology or utilitarianism pretty-much ends there, and all we have left is an appeal to conscience.
Either you agree with the premises, in which case we can debate conclusions, or you disagree with the premises, in which case we’d be better off seeing where your ethical framework and mine (natural law) happen to coincide. If you abide by pragmatism, you should favor natural law, at least in my case (and under most circumstances), because of the benefits I’ve already mentioned.
The second problem with natural law is its inherent uncertainty. Because it is difficult to determine what the proper purpose is for many human actions, there is a necessary error, a serious potential to be wrong, for any conclusion from natural law.
After all, if this weren’t the case, why did St. Thomas Aquinas, one of the chief architects of natural law, give primacy of place to the citations of Scripture, Tradition, and the Liturgy, when discussing natural law?
Thank you for your measured response,
Paul