Does comparing the total number of human neurons vs. the total number of neurons among all domesticated animals affect the moral balance between animals and people? Oxford philosopher and Effective Altruism co-founder William MacAskill engages in such neuron counting as he grapples with the issue of the moral standing of animals compared to people in his new book What We Owe The Future. I was unable to include an investigation into his ruminations on this topic in my forthcoming review of his book in Reason's December 2022 issue, so let's take a look here.
First, just how many animals are we talking about? According to MacAskill's count, people slaughter and eat 79 billion vertebrate land animals annually. The amount of biomass in land-based farm animals is 70 percent greater than that amassed in all humans. And domesticated food animals outnumber us substantially. At any one time, some 25 billion chickens, 1.5 billion cows, 1 billion sheep, and 1 billion pigs are alive. And there are 100 billion farmed fish as well. Given the rate at which these animals are bred and raised for slaughter, humans annually eat about 69 billion chickens, 300 million cows, 600 million sheep, and 1.5 billion pigs. MacAskill notes the poor factory-farming conditions under which many of these food animals are raised, resulting in, he argues, a "society-wide production of a monstrous volume of suffering." (He does not count cats and dogs, 600 million and 700 million respectively. Possibly because the lives of Fluffy and Fido are pretty plush compared to those of food animals.)
