Yes, so that means if the difference between cage-free and caged is 1 QALY then it’s as big a difference as between non-existence and healthy life. So like if I were living on a factory farm for a year, and you gave me the option to reduce my lifespan by 1 year but I get to spend my year on a factory farm without a battery cage, that seems like a reasonable deal to me.
No. 1 QALY/year is how good a normal life is. But a life could be better than that, and a life could be more bad than a good life is good. If I’d be willing to give up 10 years of normal life to avert 1 year on a factory farm, then that means a year on a factory farm is worth −10 QALYs.
What does 1 QALY per year mean? Isn’t 1 QALY per year already the difference between non-existence and an ideal, healthy life?
Yes, so that means if the difference between cage-free and caged is 1 QALY then it’s as big a difference as between non-existence and healthy life. So like if I were living on a factory farm for a year, and you gave me the option to reduce my lifespan by 1 year but I get to spend my year on a factory farm without a battery cage, that seems like a reasonable deal to me.
How does the estimate go above 1 QALY/year? Isn’t that the maximum possible?
No. 1 QALY/year is how good a normal life is. But a life could be better than that, and a life could be more bad than a good life is good. If I’d be willing to give up 10 years of normal life to avert 1 year on a factory farm, then that means a year on a factory farm is worth −10 QALYs.