If I had been in a position to design and create a world, I would have tried to arrange for all conscious individuals to be able to survive without tormenting and killing other conscious individuals. I hope most other people would have done the same.He also says that it's not possible to reconcile the fact that carnivores must kill to live with the idea of a benevolent god. He muses about the possibility that all carnivores could be allowed (encouraged) to become extinct, or to become herbivores.
Suppose that we could arrange the gradual extinction of carnivorous species, replacing them with new herbivorous ones. Or suppose that we could intervene genetically, so that currently carnivorous species would gradually evolve into herbivorous ones, thereby fulfilling Isaiah’s prophecy. If we could bring about the end of predation by one or the other of these means at little cost to ourselves, ought we to do it?In stark Darwinian terms, however, life is only about surviving to reproduce -- Darwin's dangerous idea, to quote Daniel Dennett. It doesn't matter how an organism survives, just that it does even if that involves murder and mayhem. Happiness, pleasure, the right to die a natural death, none of that counts one wit in evolutionary terms. Nor do good and evil, or selfishness or morality. These are purely human conceits.
Indeed, in his Autobiography, as recorded by Randal Keynes in Darwin, His Daughter and Human Evolution, Darwin wrestled with whether there was 'more of misery or of happiness' in the life of all sentient beings, 'whether the world as a whole is a good or a bad one'. His reply, writes Keynes, "was halting and flat, and eloquent in its weakness". 'According to my judgement," Darwin wrote, "happiness decidedly prevails, though this would be very difficult to prove.'
His reasoning was that unhappy people would be less likely to reproduce than happy people (he was thinking only of humans, not lions or crocodiles). This is of course absolutely consistent with his view of life, which was that it is only about survival and reproduction.
Anything else that humans want to lay on to this, imbuing life with purpose or morality or laws or meaning, is a creation of the human mind. It is we who give life meaning, not something we find in nature. If Jeff McMahan wants to argue that it is our moral duty to eliminate carnivory, and he can convince science and society to go along with him, more power to him.
Of course, by that reasoning we should let ourselves, as great a predatory carnivorous species as there is, go extinct.
All organisms die and mostly it's not pleasant. If teeth and talons don't do the job from the outside, parasites do it from the inside. The other ways organisms die are at least as nasty as being eaten alive.
But there is a lot of anthropocentric arrogance in McMahan's article, belying his non-evolutionary view. Why does he restrict his prescription to 'conscious' animals, and what does he mean by that.....and how does he think he even knows who's conscious?
Do fish or flies not fear? Their behavior obviously suggests that they do, even if not in the same way we do. After all, to dismiss their protective/escape behaviors as just instinct or reflex misses the point that our behavior is just neural signaling and similar mechanical processes. And for that matter, who says carrots like to be pulled up from the ground where they're just motoring along minding their own business, and then skinned and eaten (or boiled) alive.
It seems that Darwin has given everyone a license to invoke whatever arguments they want about the nature of nature. It's a problem for those who like actual science, whether or not we let ourselves believe no animal was killed in the making of that burger we had for lunch.
It won't be any better, in fact, when Monsanto actually does learn to synthesize steer muscle in a dish, because even individual cells struggle to stay alive. Life is an abattoir, even if we choose to believe that empathy and humane-ness are good, for our own psyches if nothing else.