Thank you for taking the time to read the article and responding, Elliot. Very much appreciated! 

First of all, we are in full agreement about the order of things: I am asking for more testing, and most of all for more creativity and innovative thinking to flow into this field, not for scaling anything that has not been thoroughly tested. I (foot)noted that systems thinking may change the way we think about scaling, but this does not change the order.

As for your question if I am mainly interested in EA work/talent or EA money going into diet change, I'd say: what I am mainly arguing for is renewed interest in the area, in recognition of its strategic importance. Until something worth scaling is found, the main ask would be for (exploratory) work/talent, not any big money, but of course that work still costs money. I am reasonably agnostic where that money should come from though I think it would be very helpful if EA pitched in, for the reasons mentioned - EA having higher standards of scrutiny/impact assessment, more budget comes with more responsibility - but most of all because of signaling value: willingness to spend some resources sends a message about what is valued/needed. I believe diet change work has a reputational problem within EA partly because funders seem disinterested. Offering a prize would be a very visible expression of genuine interest, and not a very costly one since the big money would only be spent if a fitting solution were found. 

On how easy/cheap it is to test new ideas and fund studies, I don't have enough personal experience to comment. Of the two RCTs I was involved with, the first was done by a professional researcher on a voluntary basis, the second by an independent researcher as part of her PHD, which was not funded by EA or any animal funds. From speaking to Seth Ariel Green, I get the impression I got a bit lucky there and that generally a sufficiently powered study that fits all the criteria would not come cheap.   

Of the $100M+ that currently should be available for diet change and animal liberation, I can't say how much of that would be available for these types of studies, but I am doubtful. The PETA part of it might be overstated (see footnote 2) and I am not clear on the source for the 50M and on how it is being spent. My guess is that a large part of it is going into online advertising and the type of work that is most visible to me (mass media, pledges). Possibly public-facing work that is not primarily directed at diet change (e.g. animal welfare messaging) could be lumped into it. Some of it might also go to street activism, though this seems to be quite low-cost.  I am not seeing money going into testing new approaches in a big way, but I would love to be proven wrong! :)

Thank you for this post! I am inclined to agree with you that EA needs to draw a lot more inspiration from systems thinking. 

Re: "A cursory google search of “plant-based zoos” brings up nothing."

Then you will be happy to learn that the Amsterdam Zoo (ARTIS), one of the oldest zoos in the world, went fully meat- and fish-free in 2022 and are working towards becoming fully plant-based by 2030. Other zoos in the Netherlands are also working on reducing meat. For an overview, see https://www.eiwitstand.nl/sector/vrije-tijd

Internationally there's also rescue centers moving that way, like the Bonorong Wildlife Sanctuary in Tasmania, which is fully vegan. 

The fact that it is not on Google does not mean it is not happening. As you say, "They don’t even need to make it a big deal – just quietly stop serving it.". But more work could be done to promote knowledge sharing on this within sectors and across our movement. Companies or institutions are more likely to adopt policies like these if they know that others are doing it too. That's why ProVeg launched the Eiwitstand.nl platform in the Netherlands