/ wrote:If by your logic, we are pretty much just animals exhibiting natural biological motives
The only point in bringing up that we are the product of evolution is to demonstrate why using a species category for anything other than classification is as fundamental an error as using race as a category for anything other than classification. Species doesn't even have an actual meaning when you're considering issues like this -- what actually is a human? Where is the dividing line between humans and chimpanzees and other animals? Chimpanzees and humans both evolved from a common ancestor. If we trace our lineage back through the generations to that common ancestor, we see a continuous line of creatures that started at something like "chimpanzee + human hybrid" (though it was probably anatomically much closer to modern chimpanzee than it is to modern human), and slowly changes to something that looks like modern humans on one side, and something like modern chimpanzees on the other side. It is purely an accident of history that the descendants of that lineage other than the currently existing humans, chimpanzees and bonobos died out. Suppose that they instead had all survived. Would you be prepared to decide where the species boundary ends for humans, and begins for non-humans? Essentially, even using the term "human" is a fundamental error when having a discussion of morality, because human is not a uniquely defined quantity. All living humans (modulo identical twins) have different genetic code, and human is a term we invented to group together people whose genetic code is highly similar but not exactly identical. The difference between you and me, and you and a chimpanzee, is a matter of degree and not of kind. It's an unavoidable conclusion of evolution. It means that BBS doesn't even know what he is talking about when he says the word human, which is why his moral system is so confused.
None of this means that creatures with the capacity to reason as highly as you or I should be exempt from a moral system. We should act morally, and the fact that we share many common characteristics with other animals doesn't change that.
Very well, but then what about animal cruelty that provides a net gain for humans?
By viciously infecting, dissecting, and grinding up a whole bunch of monkeys, we eventually got the polio vaccine, saving virtually all modern human societies from polio outbreaks. Surely this would be unacceptable to any morality based on a species' sentience or intelligence, yet it was was in humans' best interest, and besides the side effects of the vaccines, had no lasting repercussions for humans. Why or why shouldn't this be seen as a moral act to humans?
How about the countless lab rats that die every day to further science and medicine?
Great questions. Not sure I am prepared to answer them when it comes to the historical development of medicine. I do know that in modern medicine though, there's been a lot of criticism of things like medicine being tested on rats. There's actually not a whole lot of good evidence that rats respond to medicine in a similar way to humans, so there's a huge question as to whether there's much value to lab testing on rats. I can find some references to start that discussion if you want. The discovery of things like the polio vaccine may seem like an unmitigated win for the research if we completely discount the value of the animals' lives, but I'm not so sure. If we are spending many billions of dollars on research that doesn't actually work, we may be wasting a whole lot of resources on dead end research. It is possible right now that we could have had a much better way of testing medicine (like computer simulations or developing human tissue samples in the petri dish) if we had forsaken animal research decades ago and tried something different. I don't know -- I'm just sketching something out that has been argued by some medical researchers. It is not the consensus currently. But it seems possible to me that we are actually doing worse in medical research than we could be because of our animal testing paradigm, a paradigm that is an accident of history that no one has conclusively demonstrated is the most sound way to go about medical research.