if someone said to me that it should not be pursued because it was "against nature," I certainly would not find it obvious that this was wrong. I would want to know a lot more about what was being claimed before I would say whether I agreed, of course, just like with any other ethical slogan.The post to which Matt is responding says that McMahan considers various objections to his argument and that:
Among the weakest of these are the idea that implementing his proposal - even with the specific provisos he gives - would mean “playing God”, or acting “against nature”. Such lines of argument have a host of absurd implications: for instance, one might just as well use them to condemn morally innocuous practices like contraception or vaccination. They are therefore quite easily dismissed.It is not charitable to interpret reference to "playing God" as meaning some argument that implies the wrongness of vaccinations. What is going on here?
It's partly cultural, I think. A lot of philosophy, especially in England, is done by people who are openly contemptuous of religion and who have (or display) little to no understanding of it in any but its crudest forms.
It's also partly a matter of the superficiality of most contemporary moral philosophy. Although this too might be more a question of fashion than depth. Suggest that a world without tigers might be a good thing and you are provocative. Suggest that a world without contraception might be a good thing and you are an idiot. The two are connected. It is because of the perceived miraculousness of life that contraception (and all sex that excludes this miracle by design) is regarded by some as wrong. It is my perception of tigers as miraculous that makes me incapable of taking McMahan's argument seriously. In fact, taking it seriously (which seems to be what has to be done in order to get others to stop agreeing with it) can itself be regarded as an insult to nature, in the same way that taking racist arguments seriously is an insult to humanity in general and racial minorities in particular.
Two things: 1. I am not myself against contraception, but I think the argument that Anscombe makes against it (e.g. here) is interesting (and need not be Catholic or Christian--I think a Nietzschean version could be developed). 2. There is an awful lot of misunderstanding of the idea that wrong things are against nature.
Breyers ice cream advertises itself as "all natural," seemingly presupposing that this is a good thing. One might infer that artificial, or partly artificial ice cream, is not so good. You would be right, but is the point generalizable? Is opera singing morally bad? I suspect that much of it is (consider the word 'diva'--and, of course, there are male equivalents), but not because it is a form of art. Laptops are not evil just because they don't grow on trees. But no one thinks they are. Anscombe thinks contraception is evil because it is an insult to the value of life. Laptops and opera are no such thing. Is phasing out tigers? Well, it isn't an insult to the value of human life, but it does seem somewhat unappreciative of the work of the immortal hand and eye that framed the tiger's fearful symmetry. The seeming impossibility of appreciating Blake's poem while taking McMahan's argument seriously (combined, I suppose, with the obvious goodness of Blake's poem) is the kind of thing that makes me reject the argument and be depressed by it.
What does respect for life require? What is due? What is called for? Those are hard questions. But answering them requires appreciation of good things, and sensitivity. And they are not distinct from the questions, "What is life?" and "What is the value of life?", just as the question "Is torture ever all right?" quickly became "What is torture?" Ontology requires sensitivity too. And, as I've hinted, I don't trust people who can't appreciate a poem or a tiger to think well about value.