Just How Effective Does Vegetarian Advocacy Need to Be?

Follow up to How Much Does it Cost to Buy a Vegetarian?

Naïve cost-effectiveness estimates suggest that if we assume (a) a pamphlet costs 20 cents, (b) 2% of people who receive a pamphlet go vegetarian for (c) an average of four years each, and (d) the average meat eater would eat 40 animals a year, then it costs a mere seven cents to avert a year of nonhuman animal suffering on a factory farm. That’s a pretty good deal.

The problem is, however, that more work needs to be done on making these assumptions accurate – particularly (b) and (c). While more studies are on their way, it’s interesting to think just how low (b) and (c) can be while still being better than our current best option.

I take the current best option to be The Against Malaria Foundation. Perhaps there are other contenders for the best option, whether they be speculative causes or causes soon getting robust measurement, but none of them have been presented with a clear enough estimate yet to make this calculation work. Whether or not you think this is a flaw in the speculative causes or a flaw in my reasoning about causes is a discussion for elsewhere.

According to GiveWell, AMF saves a life for $2500, though this number has recently been revised down to $2000 because of the newly reduced cost of bed nets.

But, of course, “save a life” doesn’t make sense because everyone dies eventually. As the joke goes, life extension research is the only charity actually working on saving lives. But GiveWell clarifies:

If you save someone right as they exit infancy (5 years old), you’ve saved someone who probably has around a 50% chance of making it to age 60 … another way of putting this is that if you save two lives (very very rough estimate of cost: $2000), you’ve in expectation given one person a full life that they wouldn’t have had. (You’re actually getting more than this, of course, since a person has a 75% chance of making it to age 30, but let’s keep it simple.)

So, on this model, $2000 “buys” an additional thirty years of healthy life that would not have otherwise existed. Simplifying, that’s $66 to save a year of healthy life.

Now let’s go back to the assumptions.

For the same $66 you spend to save a year of healthy life via bednets, you could avert 942 years of nonhuman animal suffering on a factory farm given the assumptions we listed above.

This seems to give us a lot of room for pessimism. What if we assumed the response rate were not 2%, but instead one tenth that – 0.2%? We’d still be averting a year of factory farming for 69 cents. What conversion rate would it take to get to AMF’s $66 mark? 0.002%, or one person who becomes a vegetarian for every fifty thousand people who receive a pamphlet.

Of course, even if you’re on board with nonhuman animal suffering as something that matters, you might not think it’s appropriate to weigh a year of chicken suffering averted as equal to a year of healthy human life gained. It’s a tricky philosophical question after all. But even if you thought it took 100 chickens to outweigh a human, veg ads would still be worth it even if they only convinced one in every five hundred people.

Indeed, we can be pessimistic on all counts.

…We could think it takes 10 chickens to outweigh a human. …We could think the current studies are bad enough that they’re off by a factor of 10. …And we could think that people who convert only convert for one year on average rather than four years.

…And veg ads would still have three fold the cost-effectiveness of AMF.

Now don’t get me wrong, I actually think it’s possible that the current studies are off by a factor of 10 or more. This is why I think it’s better to study veg ads than to fund them directly.

But I don’t want this to be a cause for large despair, because veg advocacy doesn’t have to be all that good to be worth it.