Apart from fairly radical views that would prohibit any human use of any animal, I see nothing wrong with the basic idea of having dogs providing diagnostic assistance. We know that dogs can be really good at sniffing out explosives and bed bugs, for example, as we already use them for such tasks. If they turn out to be also especially good for medical diagnosis or troubleshooting, it seems like a reasonable thing to have dogs do for us. Obviously, the same rules about humane treatment for the dogs applies in these cases as for any others, and we would also want to have strong support from medical studies to confirm that the dogs really were helpful and reliable for these tasks. Even if we have only some reason to think that dogs are good at this, then they could be regarded as potentially good indicators of some problem. So if a cancer-sniffing dog reacted in such a way as to indicate that I had cancer, I think I would be well advised to go and get a check-up, even if there was not...

You are right that a longer life is not necessarily a happier life, but there are other things that go with longer life that are probably relevant to your question. I am not sure what the exact statistics are, but I see to recall that feral cats (felis domesticus) have an average life span of something like two years. The question is, what is the quality of those two years, relative to the very long average lives of cats that live as household pets? In addition to the factors that you mention, how should we think about the quality of life of an animal that has to be: Constantly alert to the danger of predators (feral and domestic dogs, coyotes, etc., who will kill cats for amusement or food). Depending on the environment, constant risk of accidents with automobiles. Constantly in search of food, with starvation and malnutrition always serious risks--especially if the cat should suffer from some injury that prevents it from hunting or scavenging effectively. Constantly...

There is always a more elegant and thorough way to address any philosophical question--that's why we're all still at it here in the world's second-oldest profession! But granting this, it seems to me that your own assessment is precisely right--our epistemic advantages over (at least most) other animals also bring with them greater ethical responsibilities. The cat can't consider whether playing with the live mouse until it dies (and then some more afterwards) is something he or she should be doing, but for us to be cruel or cause needless and excessive suffering is blameworthy. A further point, however: Some of what constitutes our greater epistemic advantages can also yield a degree of epistemic dis advantage, which is why the exercise of epistemic modesty and an open-mindedness to relevant evidence is essential to good reasoning on questions like yours. Human beings, at their best, can indeed comprehend suffering and recognize it as having negative value. Part of the way in which we...

I think it is reasonable to suppose that in order to have the character defect of being cruel (and thus, in order to act not just as a cruel thing would act, but actually to act cruelly) the being in question has to be able to do something like deliberate about the moral or ethical value of different courses of action. A hawk might be able to do something like deciding whether to attack this squirrel, but I strongly doubt that hawks can consider whether or not attacking squirrels is for the best. Now, if you tortured a mouse, I would fault you as cruel, because I regard you as capable of deliberating about whether torturing mice is for the best. But when your cat does it, the cat acts in the way a cruel thing acts--you, for example, if you did that--but the cat does not act cruelly and is not cruel, in my view.

I just answered another question related to this one. Please see my answer to that one. In gist, (1) which animals did you have in mind--"animals" is too generic for me to get much traction on an ethical issue. And (2) why do you think it is more appropriate to run experiments on mentally challenged or disabled human beings? Are (some species of) animals somhow more deserving of our moral respect? Why? Are (some species of) animals more ethically important than (some) human beings? What makes you think that? I can think of a great variety of what seem to me to be ethically significant issues that need to be visited here. One is the question of consent, which I discussed in my answer to the other question. Others include: ability to experience pain, cognitive capacities (such as memory, self-awareness), normal life-expectancy of the creature, normal "quality of life" expectancy of the creature (and how much experimentation would lead to deviation from such expectancies). I tend...

I think the PETA people will think I have a very blind moral eye, but I am inclined to think that your question makes the issue far more simple than it is. For one thing, I think there are morally significant differences between different species of non-human animals. I wouldn't think of causing gratuitous suffering or death to a wild primate, for example, but gladly crush mosquitoes to death whenever given the chance. For another (and related to the first, in fact) I think the very idea of whether animals do or do not consent and how this notion may apply to them is hardly obvious, and perhaps simply otiose. If animals (or some species) do not and cannot give consent or refuse it, then it seems to me this is not a useful more indicator for them.

Your question seems to presuppose that life itself has some value all on its own...or maybe it doesn't, because you don't mention ending the lives of plants that we eat, or bacteria that cause infections, or stinging or blood-sucking insects. I use these examples to make a point: Virtually no one believes that life of any kind should be protected. Vast resources are spent each year on exterminating certain forms of life (for example, those that cause malaria). So this leads to the more important (and more philosophically interesting) question: What lives should we value, and what is it about these forms of life that makes them valuable, whereas the others are not (or even have negative value)? Now, we often think that just because we asked the question, the burden of argument shifts to those asked. My point in this response, however, is to suggest that some reason needs to be given even for thinking that we should value lives we do not now value. Animal rights activists, as...

There is more to your question than you might think. In the case of some living things, it looks as if it is not only OK to kill them, but actually good--disease organisms, for example. I raise this kind of case to try to show that "respect all life!" is not likely to serve us very well as a moral mandate. If not, then the questions become much more complex: Which lives? Why? On the one hand, your intuition (widely shared, I'm sure) that even insects' (and arachnids') lives have some worth seems to be counter-balanced somewhat by an intuition that these lives are not worth as much as human lives (or, perhaps, those of primates). As with so many other questions that seem to require straightforward "yes" or "no" answers, I am inclined to think that the expectation of clear decision principles in these and many other kinds of cases is unwarranted. In the approach to ethics that I favor (virtue theory), the real question will not be about whether all (or some) lives are intrinsically...

The way you put this question seems to presuppose an approach to ethical reasoning that is driven by rules (imperatives). For those of us attracted to others approaches (in my case, virtue theory), it is difficult to respond to your inquiry in that form. Moreover, I think the context in which you plan to have the pet and what kind of pet you plan to have are extremely significant. Consider how differently one should answer questions like yours if the pets in question are goldfish or dogs. So let's assume you mean a very standard pet, such as a dog or a cat. Now, do you live in the country, where the dog is not going to foul sidewalks, potentially menace pedestrians or bicyclists, be at risk for being hit by a car (which could also put others at risk, from drivers swerving to avoid hitting your pet), or attack others' pets in the street? If the context is a city or similar, then it looks like you will be obliged to keep your dog leashed at all times when outside the home. In the case of a cat, it...

You make several points here, and I may not respond to all of them. But first, there may be any number of reasons why people regard non-human animals as not meriting the same degree of moral regard as human beings. I think (given the format of this site) it is probably best here simply to provide some basic indication of how this might be appropriate, so think of it in terms of how we value reciprocal relationships. We value our pets, in this way of thinking, because they really do reciprocate our attentions and affections--at least, as far as they are able to do so. But the reciprocation that is possible between human beings and their pets is limited--far more limited than the reciprocation that is possible between human beings. So it may not simply be a matter of valuing certain traits (e.g. intelligence) in a prejudicial way, so much as the ways in which such traits allow for richer (and more reciprocal) relationships. As for religion's regard for non-human animals, it will really depend...