[Question] Consequentialist veganism

I may be wrong, but I think the following is a mainstream position in rationalist circles: even people who care about animal welfare don’t have particularly strong moral reasons to personally switch to a vegan diet.

I haven’t seen a fully fleshed-out defence of this position. I can think of a few possible arguments, but none seem convincing:

  • Any single consumption decision probably won’t make any difference

    • That is true, but my model of how this works is that, very roughly speaking, each decision to abstain from consuming x grams of [animal product] has a 1/​n chance of causing some demand threshold to be crossed, such that x*n fewer grams of that product are produced in the next cycle. The upshot is that, in expectation, your vegan diet reduces the number of animals put through the agricultural process (or, in the case of e.g. wild-caught fish, the number being caught by. humans) by roughly as much as you would think if you simply added up your counterfactual consumption and divided it by the number of animals required to produce it.

  • The only way to get rid of harmful animal agriculture is through mass persuasion and/​or coercion and/​or technological progress, not individual (non-)consumption

    • Yes, but so what? This is clearly not an all-or-nothing cause; each instance of suffering matters, regardless of how many other instances exist. Nor are personal consumption change and social/​technological change mutually exclusive or even conflicting.

  • There are higher-impact uses of your (time/​energy/​money/​etc.)

    • Maybe—though I suspect that the rosier estimates of e.g. the impact of donating to an advocacy organisation tend to be significant exaggerations—but most of us do not have good reason to treat this as a zero-sum game in which each attempt to do good in the world must crowd out another. For one thing, we’re nowhere near putting all available resources into our efforts to do good, so we can simply choose to expand that budget. For another, our psychology is complicated, and making a moral effort can just as easily increase our capacity to make further such efforts as deplete it. (As for money in particular: unless you’re already eating unusually frugally, you can probably find a healthy vegan diet that doesn’t require significant extra expenditure.)

  • [Something about indirect effects on e.g. wild-animal suffering or insects]

    • I don’t dismiss these arguments on principle. But their force is attenuated by uncertainty, so they need to be very strong to overcome the more obvious direct effects.

Then there are arguments over which agricultural-animal lives are worth living. We can differ on that question for pretty deep reasons, so it’s harder to usefully argue about. I certainly acknowledge that agricultural-animal lives worth living are possible, but I think they’re much rarer than we would like to think.

There’s also an argument that some hunted animals, for example wild-caught fish, might not be significantly worse off than those that die a natural death. I could be (and selfishly would like to be) convinced of this; I’m well aware that natural lives often suck and natural deaths usually suck. But my understanding is that the methods of catching and killing fish at scale tend to be pretty horrible even compared to a natural death. (And when I looked for more ethical sources of fish, it seemed like all anyone cared about was things like dolphin safety, not humane treatment of the fish themselves.)

(At the meta level, I also think we should try to apply extra scepticism when evaluating arguments in favour of conclusions that are very convenient to us. Even rational people are prone to rationalisation, and it’s very very tempting to suspend disbelief a little bit when evaluating an argument against making a difficult change, and apply an extra-critical eye to arguments in favour of making that change. This is only relevant at the margins, where there is significant uncertainty and judgment calls have to be made, but I think that does apply here. )

So anyway, with all of that in mind, can anyone convince me that personal veganism is unnecessary, even taking for granted the following?

  • animal welfare matters a lot

  • animal agriculture is overwhelmingly net-negative for animal welfare

Arguments in the other direction (i.e. in favour of veganism) are of course welcome too.