Summary: Various people (Hurford, Tomasik) have tried to estimate the typical animal welfare cost of a carnivorous diet. These costs have encouraged EAs to become vegetarians or vegans, and EAs particularly focused on animal welfare advocate that others (including EAs) should reduce their consumption of animal products.
Closely following an estimate by Kaufman, I consider the face value of abstaining from dairy or abstaining from all animal products in terms of donations to ACE-recommended animal welfare charities: <1 cent per year given to The Humane League would offset typical dairy consumption, and <$1 year would offset a typical American’s consumption of all animal products. Thus the emphasis on dietary change intra-EA seems misplaced: it is extraordinarily low impact compared to other means to helping animals.
Introduction
Industrial agriculture produces vast amounts of animal suffering: not only are billions killed each year, but their lives are often horrible – so much so that informed observers consider their lives to be not worth living. Given this suffering is generated to satiate human’s relatively trivial desire to eat meat, eggs, and dairy, reducing consumption of these products can relieve vast amounts of suffering. Many effective altruists think this (and animal welfare) is the most important thing to work on right now, and encourage others to become vegetarian and vegan. Many other effective altruists, even if they aren’t primarily focused on animal welfare, are vegetarian and vegan due to this reasoning..
How much is being vegan worth?
Effective altruists like quantification and trying to weigh the relative importance of different courses of action. This gives surprising answers in case of veganism.
Working out exactly how much suffering is hard. Happily, much of this work has already done by Brian Tomasik on the ‘suffering per calorie’ estimates of animal food products, and subsequently by Peter Hurford on the suffering typically accrued by a typical American’s diet. Jeff Kaufmann recently used these figures to compare the ‘value’ of abstaining from dairy in terms of a donation to AMF. A precis:
A typical american dairy consumption is 1/45th of a dairy cow’s annual output. Thus consuming dairy for 45 years is approximately a ‘single year of cow life’ (ignoring elasticities). $100 is thought to avert 1 DALY if given to AMF. So if you think a year of cow life averted is about as valuable as one year of human life, then a couple of dollars given to AMF approximately offsets the harm of dairy.
This calculation is necessarily rough, and perhaps the principal problem is comparing ‘years as a dairy cow’ versus ‘years as a human’. Many people will say that human lives are worth more, but others (particularly EAs interested in animal advocacy) might argue that averting years of dairy cow life is more valuable to adding years of human life.
The advent of Animal Charity Evaluators allows a more ‘apples to apples’ comparison, as they offer rough estimates of how effective their charities are in terms of ‘animal lives in agriculture’ averted, which is about the same outcome as we expect from reducing our consumption. These figures are remarkably high: ACE estimates the Humane League as averting 3.4 lives for every dollar spent. It rates Mercy for Animals and Animal Equality International even higher, at 8.8 animals/$ and 10.1 animals/$.
A comparison between donations to THL and abstaining from dairy is instructive. 1/45th of a cow life per year, divided by 3.4 lives per dollar:
Price (in THL donations) of dairy = 1/45 years / 3.4 years/$ = $0.0065
Less than a cent per year to THL (the least cost-effective of ACE’s recommendations) does as much good as abstaining from dairy from the same period, and this might be conservative (we’ve assumed that animal lives only last one year, inter alia).
Dairy is the least harmful of animal products in the typical diet. Consider instead going from a typical american diet to veganism. Peter Hurford helpfully provides the following estimated relative harms of different animal products in the typical american diet:
- Giving up beef is ~2.1x as important as giving up dairy.
- Giving up beef is ~1.9x as important as giving up turkey.
- Giving up pork is ~2.9x as important as giving up beef.
- Giving up chicken meat is ~11.3x as important as giving up beef.
- Giving up eggs is ~11.8x as important as giving up beef.
- Giving up aquacultured fish is ~6.4x as important as giving up beef.
We can convert the relevant foods into ‘dairy equivalents’.
Dairy - 1 Beef - 2.1 Pork - 6.1 (2.1*2.9) Chicken - 23.7 (2.1*11.3) Eggs - 24.8 (2.1*11.8) Fish - 13.4 (2.1*6.4) TOTAL - 71.1
So the typical american diet is 71.1 times worse than only consuming dairy but abstaining from meat and eggs. We can recalculate the value of turning vegan in terms of yearly THL donations:
Price (in THL donations) of veganism = 1/45 * 71.1 / 3.4 years/$ = $0.46
So being vegan for a year is about as good as giving 46 cents to the humane league.
Sources of uncertainty
This seems remarkably cheap. Should we believe this calculation?
I have made a few short-cuts, and a more careful calculation could be made (perhaps recalculating the animal welfare costs from Hurford rather than taking the bottom line estimates, or dis-aggregating ‘animals’ when looking at the benefit of abstaining from dairy alone). However, it the ‘bottom line’ figure isn’t sensitive enough to these factors to be driven up by several orders of magnitude. Hurford also estimates the typical American diet causes 5.5 years of animal suffering per year. Using this directly gets a factor of 4:
Price (in THL donations of veganism = 5.5 years/3.4 years/$ = $1.62
Further, several elements of the calculation were conservative: I’ve ignored elasticities (which would reduce the amount of animal suffering dietary change would avert), I’ve assumed that all animals saved would live for a year, and I’ve picked THL instead of 2-3x better performing AE or MfA. Scott Alexander has made a similar calculation to mine using similar data, and gets similar ‘bottom line’ figures.
Perhaps weakest component in the calculation is the cost effectiveness of the animal charities. One may think the estimates are too good to be true. Even if one cannot see any obvious feature of over-estimation, regression to the mean means that the estimated-to-be-best charities will be generally overestimated, and this effect can bite particularly hard if the distribution is log-normal or broader.
Is veganism worth it?
Taking these calculations at face value suggests individual dietary change is unimportant, with an equivalent donation value of a handful of dollars each year. Given most people would prefer to keep their current carnivorous diet for more than this amount, this suggests offsetting donations are much better for most than diet change. (Of interest, if milk substitutes are even 1 cent more expensive over the year, then returning to milk and donating the difference seems a better strategy.)
If one is pessimistic about the estimates ACE gives, and anticipates a 3 or 4 order of magnitude correction, then the price of veganism does rise to the level where people might prefer to change diet rather than give moral offsets. However, most animal focused EAs I’ve talked to seem optimistic that ACE’s estimates are not dramatic over-estimates. This optimism seems incongruous with their eagerness to get EAs and EA events to be vegan: persuading them to give their pocket change to THL seems much easier (and better for animal welfare!) than getting them to change their diets. Dietary change looks like a very ineffective intervention.
Sundries
I foresee two main objections, given the remarks Jeff’s post gathered.
The first is that unlike donation targets, veganism and giving money to THL are not mutually exclusive, so there is no trade-off – just do both! Yet although veganism may not draw directly on our donation budget, it may plausibly draw on our budgets of self-sacrifice and self-control. There are other unpleasant actions we could take which are independent of donations (having cold showers to reduce energy expenditure and thus climate change), which most of us intuit probably aren’t worth it in terms of indirect costs due to their limited impact. I aver that for most people changing their diet, given the extremely low monetary value of an offsetting donation, falls below this threshold. (For those for whom it doesn’t, go vegan!)
The second that this analysis only tries to model ‘first order’ impacts. Being vegetarian or vegan might have a larger impact in terms of persuading others to become vegetarian or vegan, and generally act to signal dismay at animal agriculture. It looks hard for an animal welfare advocate getting any traction if they eat meat. These ‘second order’ effects are hard to quantify, but I struggle to think they would be worth more than 10x or 100x the ‘direct impact’ of not eating animal products for most people who aren't spending most of their energies being animal advocates. I have been a vegetarian all my life, and I have mentioned it in conversation less than 50 times, and I doubt much more than half the people who know me also know I’m a vegetarian, and much fewer the reasoning why. The amount of ‘second order effects’ of my vegetarianism on animal welfare are wholly trivial, and I doubt I’m wildly away from the population mean in terms of second order impacts.
This is a really good article, and I do find the perspective advocated compelling. However, I would like to voice some worries.
Anyone not committed to an consequentialist mindset is likely to take serious issue with someone who eats meat but donates to charities that encourage other people to give up meat. In general, advocating that someone else make a sacrifice that you aren't willing to make is seen as hypocritical and lacking in integrity. People will criticise you and perhaps, by association, effective altruism.
I'm sceptical, psychologically, that this kind of reasoning will make people donate more in total. I worry the main effect will be that they eat more meat.
This style of argument worries me more generally because rich people will very often be able to compensate for terrible things they wish to do by donating more money to charity. E.g. cheat on your partner and donate to a charity to encourage stable relationships. This buys into the negative image of EA as allowing rich people to justify themselves morally.
Perhaps we should instead claim that the strong reasons to be veg'n aren't affected by the existence of other great ways to do good. Avoiding thousands of years of terrible suffering by going veg'n for life is just a great thing to do: anyone who can should make that sacrifice.
Agree - it's worth pointing out that 'meat offsetting' isn't obviously morally OK unless you're a consequentialist. It's analogous to a case where you kill one person then pay someone else not to kill a different person - and you'd only have to donate $3500 to AMF per person killed, bargain!
(unlike CO2 offsetting, where the overall level of CO2 is reduced and fewer ppl are harmed).
Ben, actually CO2 offsetting suffers from some similar problems, but obscures the fact. When you emit carbon dioxide those emissions will go on to harm particular people. When you buy offsets that will avert emissions that would have harmed different people.
So it's analogous in that way to shooting randomly into a crowd, and then offsetting by paying others not to shoot into the crowd. Some reasons we react differently for CO2 are that the victims are distant, aren't identifiable, and the mechanism is further from direct physical force.
What's this claim based on?
Harm from weather events: heat stroke, storms, crop damage. Plus the butterfly effect.
That only seems to show that emissions do harm. Not that the harm is so finely individuated. fwiw there are reasons to doubt the butterfly effect works in the same way given quantum mechanics
I'd be interested to hear Carl's response, since this is an interesting test case for the harm-avoidance moral principles at issue.
CO2 offsetting is an ex ante pareto improvement, whereas killing one person then paying someone else not to kill more than 1 person isn't. I was trying to say the meat offsetting example could be seen as more like the second. You could think both are problematic though.
Interesting. Nonetheless, people buying carbon offsets don't think that their pollution is seriously harming certain people which they're making up for by helping otherwise. So they see buying carbon offsets as very different from buying the sort of 'murder offsets' that Ben mentions.
For the consequentialist, offsetting is a bad perspective anyway - unless you have an odd arbitrary setpoint above which consequences don't matter, you should neither kill someone nor ever refrain from donating to save lives.
Meat consumption is different because it can actually affect the extent to which one is able to be ethically productive.
It would be neat if people could engage in discussion instead of downvoting, but whatever...
Perhaps you could further describe 1) Why you think that offsetting meat consumption is different from offsetting killing a person 2) How meat consumption can "affect the extent to which one is able to be ethically productive"
For me, these kinds of discussions suggest that most self-declared consequentialists are not consequentialists, but deontologists using consequentalist decision making in certain aspects of their lives. I think acknowledging this fact would be a step towards greater intellectual honesty.
Many EAs don't self-declare as consequentialists. And even if you think consequentialism is the best guess moral theory, due to moral uncertainty, you should still care about what other perspectives might say. https://80000hours.org/2012/01/practical-ethics-given-moral-uncertainty/
"Perhaps you could further describe 1) Why you think that offsetting meat consumption is different from offsetting killing a person"
Because meat consumption has the potential to save money and/or time for the average person, which murder doesn't.
"2) How meat consumption can "affect the extent to which one is able to be ethically productive"
As the OP, Katja Grace, and others have pointed out, if being vegetarian incurs any social or monetary costs in the range of under, say, $100 a year, then it's far more inefficient than donations simply to animal charities, while human poverty charities and existential risk charities could do even better. Personally, I save $100 a month by living in an apartment without a kitchen where I can't cook meat substitutes, I save an additional $10 or so per week on groceries (based on comparison between my expenses when I was living vegetarian and now), I spend less of my time cooking, and my diet is more complete.
Well, too bad, because I am a consequentialist. <<
To clarify, this remark was not directed towards you, but referred to others further up in the thread who argued against moral offsetting.
Oh, right. Yes that's true, sorry for misunderstanding.
People who change their diets because of ACE-recommended charities will also have second order impacts (although you would have to change some of the calculation to distinguish between animal product reduction and veg*nism). So this would appear on both sides of the equation, and wouldn't clearly favor personal diet change over donation.
One could make an argument, and I have seen it claimed, that the signalling benefits of veg*nism are far greater in the effective altruism community than elsewhere. But selectively invoking second-order effects for one option but ignoring them for the other biases the estimates.
Separately, the average medium-run second-order benefits of veg*nism as such can't be that huge, given that there are already hundreds of millions of vegetarians in the world. If the average second-order effects of vegetarianism had benefits 100x greater than the direct dietary effects, then the total benefit would be larger than eliminating all meat consumption worldwide. And yet that hasn't happened, so the average second-order benefits have to be much smaller, although they will be higher in particular circumstances.
Hi Carl,
Not sure I follow. How do we know that the hundreds of millions of vegetarians are not the 2nd order effect of a few millions being persuaded to give up animal products?
Having only vegetarian or vegan food catered at big events is visible to everyone there, and might get comments in the news media if there are reporters present, but involves a lot less dietary change than eating veg*n all year. That could be 3-4 orders of magnitude right there, for the more limited stance 'if people want meat at a few conferences per year, they have to bring it separately rather than have it visibly catered.' That's why I encouraged EA Global not to serve meat, even while thinking that your point about overemphasis on personal diet is a good one overall.
If almost all the effects of of going veg*n year-round are symbolic, then there will be low-hanging fruit of symbolism orders of magnitude more important than the typical meal.
First off, thanks for the article. It's an interesting perspective and it's well calculated and formatted.
However...
I definitely agree that the ACE numbers should not be taken literally, as there are fundamental problems in the underlying studies from which those numbers are derived. The truth is we really don't know even if they're off by like four orders of magnitude. So maybe it takes $5 to create a vegetarian, but it might also take like >$5000.
While I'm at it, it probably is best not to take my numbers too literally either, as they were put together pretty hastily, I think I missed some considerations, and some sources disagree.
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Disclaimer: I am a board member of ACE. This opinion is my own, not necessarily the position of ACE or other ACE staff / board members.
If the point estimate or expected value given the uncertainty and reasonable priors would be a lot lower, then the reporting should reflect that, e.g. "this methodology says $X per animal prevented from existing, but different members of our team have expected values of $X, $2X, $100X, and $5000X when taking into account priors, other evidence, regression to the reference class, winner's curse, etc."
GiveWell publishes a cost-effectiveness spreadsheet at giving season where various GiveWell staff members input their own estimates in charity comparison.
I agree this would be cool for ACE to do. I don't know what the values of N*X are for other staff and board members, though.
I personally think that the cost-effectiveness figures for veg*n outreach are implausibly positive. I don't think it's plausible that converting someone to vegetarianism through favoured methods like leafleting is many orders of magnitudes more cost-effective than these figures (in which case it'd cost mere cents). But, given our current evidence, I do think it's plausible that leafleting is many orders of magnitudes less cost-effective than claimed. Peter says "maybe it takes $5 to create a vegetarian, but it might also take like >$5000" - at which points perhaps simply paying people in poorer countries to go veggie would be more cost-effective, as PETA controversially did in Detroit.
(Unfortunately I don't have time to go into more depth on this issue. I'm far from an expert on it anyway!)
See also the discussion of this post on the EA Facebook group.
This annoys me about the stance some vegans take, and I'm glad you've quantified it. I'd always figured the impact of being vegan was relatively low compared to donating to effective animal organisations, but am a little shocked it's THAT low.
I've argued that vegans could do a lot more good by eating modestly and donating the difference to say the Humane League than being vegan and eating at fancy restaurants all the time. Of course, the ideal case is to do both (be vegan and donate). The same applies for people who think they are doing a lot of good by rescuing say a cat and looking after them. This may be true, but cats need to be fed meat, and the running costs of having a cat could save many animals through effective donations.
This is a very hard sell for deontologists, and in my experience most vegans who aren't also effective altruists are deontologists, but morality doesn't begin and end with not eating meat.
As for whether being vegan is worth it, I can't say I spend any more now than I did when I was an omnivore. In fact I think I spend significantly less, considering how much good quality meat costs, both at shops and at restaurants.
I think this concept leaves open the possibility of people 'offsetting their meat consumption' with donations in a similar way people offset their carbon credits when flying in a plane. I don't have the figures but in many cases it is more effective to fly somewhere and offset your carbon credits than to catch a train, which takes far longer and costs far more. Most people I've pitched 'offsetting meat consumption' to are horrified by the implications to society. Perhaps not something we want prevalent long term, but it might take off faster than mass veganism would otherwise? Thoughts?
Overall I'd be cautious. This is the sort of thing that, if it went mainstream, would be taken by the non-vegan part of society as an excuse to not eat meat, but I don't think that would correlate with an increase in donations to effective animal charities.
The end goal is obviously to have everyone go vegan to eliminate animal suffering associated with consumption.
Let's do a thought experiment and say that the whole world decides to eat meat and offset their meat consumption with donations. The effectiveness of such donations would plummet, as it's becoming harder to convince people to go vegan. I'd see this as reason enough to be cautious.
That would increase the price of offsets, until you reached a level at which the cheapest offsets were things like in vitro meat research, or the new chicken-sexing technology that allows sexing of chicken eggs to avert the killing of billions of male layer chicks. Although those might be cheaper offsets than veganism promotion today already.
Scott Alexander:
"once they’re exhausted, the offset price will rise, and people for whom vegetarianism is only a mild inconvenience will find themselves preferring to become vegetarian themselves rather than paying."
Or they'll just give up on the whole concept entirely, not wanting to pay $X OR give up meat.
First of all, thanks for taking the time to calculate this for the rest of us! I was wondering about this myself.
One observation: Peter Hurford's standard American diet doesn't include shrimp and wild fish caught to feed aquacultured fish. That's the vast majority of all animals killed. ACE, on the other hand, does, which yields 262-406 animals killed per omnivore per year instead of ~30. This higher figure seems to be the basis of the 3.4 animals saved per $ for THL.
If we correct for this, we come out at 262/3.4 = 77$ or 406/3.4 = 119$ to save as many animals as a vegan does per year compared to an omnivore. (That's 167x to 259x as much as the 0.46$ estimated above, which can't be accounted for by wild fish and shrimp. Why does this method yield such different results?)
There are many uncertainties though, e.g. does veg advocacy actually reduce people's shrimp and fish consumption as much as their meat consumption? Or do some substitute fish and shrimps for meat (some 'vegetarians' still eat fish!)? That would completely turn the calculation around.
Thanks for the numbers! I’ve made a similar calculation using cost-effectiveness estimates and estimates of animal lifespans form ACE and disability weights from Norwood in my cause selection article. There’s also an accompanying spreadsheet.
Using the estimate that “a vegetarian saves between 371 and 582 animals per year” from Counting Animals, one year of vegetarianism is equivalent to some $50–80 donated to the average ACE top charity.
Due to Norwood’s disability weights it would be particularly silly to avoid milk since he estimates a positive quality of life. Brian critiqued these numbers, but I’m not sure if he would substantially disagree with this particular estimate. It’s probably not terribly relevant in a negative utilitarian framework either.
I find these discussions of moral offsets somewhat disturbing, re: Tom_Davidson's third point. Can we host a dog fighting ring at EA Global next year as long as half the buy-in goes to the Humane League? Can we get trafficked children to cook our food as long as we give a nice plump sum to SCI?
I think the analysis is fine, and it's good to know the real impact of certain actions (like going vegan). But then to take it a step further and say, well, I can just skip acting morally in this case and offset that with a donation seems to miss the mark. How far are we willing to go, as a community, down this road, and where do we draw the line?
The only clear and decisive way out is to accept that your life should be maximally ethical. So you shouldn't go around pursuing wanton acts of vice, but you should make whatever decisions are necessary to maximize your overall ethical productivity.
Most people who go vegetarian find its very very little effort to be 90% vegetarian after a year or so. To me this warns against the view that people will give extra because "they haven't made the sacrifice of becoming veggie". Very soon the sacrifice becomes a habit and the claim that charitable donations are affected becomes even less plausible.
I'd be interested to know if anyone has given more money because of this thread. I know that i'm more willing to eat diary products and have read others saying it made them happier eating meat.
Good: as long as you're comparing apples to apples, keep it that way. It applies equally to reduction in meat demand whether from personal choice or advocacy.
... that doesn't seem to make sense... we're trying to prevent animals from existing, right? The relevant time factor is lifespan prior to slaughter, which was factored by Peter into his analysis (and by Brian Tomasik into his own).
Ah, but the same will occur for anyone who has been persuaded by vegan advocacy efforts to go vegetarian or vegan, so as long as we're still comparing apples to apples, this should also be excluded from the analysis.
One might say "but we're effective altruists, our advocacy and role-modeling is much more important than random other people's role modeling." But the opposite may be the case: creating role models and signalling in new communities and new groups of people may be much more important per person converted than creating role models and signalling in a highly rationalist and self-reflective community where all these ideas have already been exposed and discussed.
This is the big question and it comes down to people's psychology.
Some people really try to maximize their total productivity and contributions, and do so quite rationally. For them this sort of thinking really makes sense. However, I think the majority of people in effective altruism still spend significant amounts of time and money on non-optimal items and activities. Therefore, the right decision in such a case is more nebulous.
I'm sure many people will raise objections to your calculations and numbers and make different claims about whether or not EAs ought to be vegan/vegetarian. However, the key takeaway will probably stand regardless: when it comes to improving the lifestyle of the EA community to be more ethical, diet change is clearly not a low-hanging fruit. If we want to apportion praise and blame to people on the basis of the consequences of their decisions, then career and financial decisions are much more significant than diet choices. I don't mean to say that we should be aggressive about people's career and financial decisions, nor do I mean to say that it's wrong to make claims about what diets EA folks should adopt, but we need to put things in perspective before people get flustered based on these kinds of issues (which, I recall, happened a little bit when Katja Grace posted a blog article about this issue).
Thanks for the analysis.
Of possible interest: here's a link to Katja Grace's post on a similar issue and the accompanying discussion.
On further thought, also important to note that animal cruelty isn't the only reason to be vegan. Environmental impact and health considerations also play a role. Is there any way to include these in the calculations?
But you shouldn't include those because you're comparing 'apples to apples'. If other people save more of the environment by being vegetarian then that's just as good as you helping to save the environment.
I'm not sure I fully understand your comment. By being vegan you achieve all 3 at once, so the cost benefit analysis isn't as simple.
I think kbog's point is that Greg appears to be comparing 'person x going vegan' with 'person x donating $y that causes z other people to go vegan'. If going vegan has other benefits, e.g. environmental benefits, those will happen either way and don't effect the comparison unless we have reason to think person x going vegan is particularly valuable compared to a random individual.
Ah of course, I understand now. A big oversight on my behalf, thanks for clearing that up!
And converting other people to be vegan also achieves all 3 at once, except it does so to a much greater degree.
I do not actually get the comparison. You do not have to decide whether you change your diet or donate money to animal charities, you can actually do both of it.
Additionally, you did not consider, that changing your diet has an impact on other people who see that you went vegan and it might make them vegan as well.
Apart from the fact, that it seems unlogic to donate for a charity which aims to reduce animal suffering and at the same time buying products which cause the exact suffering seems wrong.
It is like deciding between donating to AMF and at the same time as it brings pleasure for you to destroy all the distributed nets cause it brings you joy.
What has not been considered is the huge consequences of the consumption of animal products when it comes to health. Shouldnt EAs live healthy and have a healthy diet in order to not have high healthcare costs in the long run? If I want to live healthy to not have bad living conditions because of diseases I cant prevent them with a healthy diet. It is pretty clear, that for example dairy increases your risk of the main causes of death.
Additionally, the comparison between the cost of dairy and a milk substitute ist just too lazy. When you compare vegan to omnivorous diets, the healthy vegan diet consists of whole grains, fruits and vegetables. These are not only healthier und better for the environment, but they are way cheaper. It is more expensive to buy dairy and chicken instead of buying potatoes and brown rice.
You might want to think about this.
I think there is a mistake in the calculation: Price (in THL donations) of veganism = 1/45 71.1 / 3.4 LIVES (instead of YEARS)/$ = $0.46/life. Assuming most lives are chickens who live on average 1/10 of a year (5-6 weeks), we get about $5/year vegan. This estimate is in line with ACE (https://animalcharityevaluators.org/research/donation-impact/) and Counting Animals (http://www.countinganimals.com/how-many-animals-does-a-vegetarian-save/): 400 lives/year vegan divided by 76000 lives/1000$= $5/year vegan. The latter is the marginal impact, which is slightly better than the average in the US: $50.000.000/year donations to vegan and animal farm organisations divided by 5.000.000 vegans= $10/year vegan. The offset price can increase in the future if it becomes more difficult to convert people to vegnism (if the low hanging fruit of meat eaters is already converted)