Robin has long had a possible moral defence for meat consumption on his personal site. The basic idea is this: If everyone switched to vegetarianism/veganism, we would convert land that currently supports farm animals into land that supports plants.
If you were prevented from eating meat/dairy for some long period of time (say a year or even 10), I doubt you would willingly lose a finger in order to start eating meat/dairy again.
I think the relevant empirical question is whether people who refrain from eating meat or dairy are on average less happy (or successful, or whatever other metric) than people who do eat those metrics. Trusting your own guess at what the disutility might be is flawed, you are biased because your current self cannot identify with such a change in identity but the consequences of actually making the change may be minimal or positive rather than negative.
Yes, I'm aware some people think it's important. I would argue that they're wrong - their priorities are messed up; humanity should ensure its own survival first.
Please read this piece. It addresses why population expansion may be a bad idea.
I think there's some confusion as to "utility".
If you don't care about animals, it is clear that eating meat is okay, not because of the logic of the larder or something to that effect, but simply because you don't care about them.
If you do care about animals, and you think, for example, that not torturing animals is better than torturing animals, you have to have some preference ordering of happy animal, sad animal, and no animal. Not having such an ordering would leave you open to a money pump.
Perhaps I'm misinterpreting something, but it sounds as if people are saying that their_utility(happy animal) = their_utility no animal) and their_utility(sad animal) = their_utility(no animal) on the basis that, since the animal doesn't exist, it can't be better or worse. People are still saying their_utility(happy animal) = their_utility(sad animal).
Let me perform a thought experiment: I decide to raise a happy cow, but then I ask you if you mind of I don't raise a cow. You tell me that you don't mind. I then decide to raise a sad cow. Again, you tell me that you don't mind. You then ask if I'd mind treating the cow better. I tell you that I do mind, but I'll be willing to do so for $10. You pay me, and we start the cycle over. You wouldn't do this in real life, of course, but I'm not sure I understand why. On which step did I err?
Good FOR WHO?
If more animals gives us utility, by all means, it's an opportunity cost. This has other implications, however, and generally seems like an ad-hoc hypothesis designed to render factory farming excusable. Why would we value having as many animals living as possible?
THOSE ANIMALS clearly get utility by existing - unless, as this article postulates, they get negative utility, but lets ignore that for the moment. Since THOSE ANIMALS will, by definition, not exist if we do not create them, the opportunity cost to them is purely hypothetical, an has no moral force - unless you care about the wishes of all hypothetical agents, I suppose, but that has it's own problems.
OK, I've been thinking about this problem a bit more.
My existence gives me utility, because I can act to improve the world. Also, I enjoy living. Thus destroying me is an opportunity cost to me.
Another agent's existence may give me utility, if it acts to shape the world according to our shared goals. It may also give me utility simply by existing. Thus, failing to create it is an opportunity cost to me.
Any agent's existence grants it utility, because it can act to shape the world. It may or may not gain utility by existing. Regardless, destroying an agent is almost always an opportunity cost to it.
If I care about any agent fulfilling it's goals - because I'm an altruist - then destroying it is also an opportunity cost to me.
If I care about ANY agent's goals being fulfilled, then any agent failing to exist is an opportunity cost to me, although it is not as great as the failure of an agent that considers the current world a perfect fulfillment of it's goals, forever, is.
It is only in this last case - where what we value is the total number of agents succeeding at their respective goals - that an agent failing to exist is an opportunity cost to us, although it's not as big a cost as failing to create an agent that consider the world as it is the perfect fulfillment of it's goals.
I find this extremely unlikely, but you might have better luck with Buddhists who think not caring about a problem counts as solving it, so we should all strive for apathy.
An opportunity cost is not an actual cost, and is never suffered. It's just a way of moving the zero point to aid in thinking.
If you want precision: While nobody is hurt by not existing, there would be good if someone does exist. Good is better than neutral, so go with existing.
> An opportunity cost to who?
It's an opportunity cost, not a true cost. It's simply the lack of a benefit. If they existed, there would be someone to benefit, thus there's opportunity cost to not existing.
An opportunity cost to who? Ghosts?
It's not trivially wrong, but it's not trivially right,either.
Ergo, since there's no opportunity cost in not existing (due to the absence of an agent who might suffer the cost), it isn't good to exist. (Which isn't to say that it's bad to exist, a proposition that could be refuted as easily.)
ADDED. To Muga Sofer. Seems trivial to me—if you proceed from the definition of opportunity cost rather than from a vague intuition about some ethical purpose the concept supposedly serves. That is, the conclusion may not be trivially false, but the reasoning surely is trivially invalid. But "trivial" or not, applying "opportunity cost" to situations where no agent exists is a straightforward category error.
If it's good to exist, then there is an opportunity cost in not existing.
The idea that we should take into account the wishes of agents who don't exist, never will exist, and have never existed is ... far from obvious.
"Moral realist" is not identical with "moral".
In other words, having goals does not require believing them to be magic.
Thank you for writing about Farm animals. Human beings are monsters in their treatment of animals. Factory farms need to be abolished! I have come to the conclusion that 6 billion (and growing) humans are definitely a cancer on this planet.
Why do you say that? I'd guess it's around neutral.