Is it ok to kill ants for fun.

No.

I think there's a very basic sort of respect for living things that's lacking in someone who smashes ants just for fun. This isn't respect in the full-blown sense Kant had in mind when he said persons are owed respect, but it's not completely different either. Ants aren't just rocks or clumps of dirt, but little centers of living (whether sentient or not) that ought to be left alone if they're not doing any harm. Which means: it's different if they're biting your toe or eating your lunch. The kid who smashes ants for fun is committing a little sin right then and there, I think, but I'd also worry about possible follow-ups. What other living things may he or she see as totally valueless and disposable? Perhaps we don't need to worry that ant-smashers will graduate to people-smashing, but I'd worry about associated disrespectfulness toward nature and other animals.

I am not so sure of Jean's response. Ants are indeed little centers of living, but then so are flowers and I would not necessarily think it wrong to pull the petals off a daisy, for example, and often do. Pain does come into it, and if ants feel pain, and might be able to feel pain, then killing or injuring them is clearly problematic, unless they are attacking us, perhaps. Even if they are attacking us, it is not through any desire to harm us, or to deprive us of our picnic, and we might well feel moral qualms at squashing them, if they can experience pain as a result. Here the type of ant is at issue. If it is a large tropical ant who has sunk his pincers in our big toe, then perhaps killing it is the only means of removing it, but in most European cases nothing so dramatic is likely to occur. If they could feel pain, and I understand this is something that is at present unresolved, then we should lay off them. Why not destroy a flower instead?

I would be reluctant to decide all questions about the treatment of animals on the basis of pain and pleasure. That standard leads to some strange results. Say you put a wild bird in a cage, and you anticipate that he will suffer from the frustration of not being able to fly. So first you give him No Fly Drug, which is guaranteed to eliminate his frustration. Or perhaps you keep your dog in a crate 24 hours a day, and after a year she completely gives up, zones out, and stops suffering. Does her adaptation now give you an excuse to leave her there forever? The offense in each case is not a matter of causing pain (or decreasing pleasure) but--intuitively--a matter of being disrespectful.

I'm inclined to think we owe respect only to things at least capable of consciousness, though what we owe them is not exclusively sensitivity to their pain and pleasure. So if ants have no conscious life whatever, they do have the moral status of flowers, and nothing we ever do to them is disrespectful. But is that the case? Nobody really knows for sure. An interesting book that will make you think twice about the mental lives of insects is Animal Architects, by James and Carol Gould.

I don't think those counter-examples are very helpful. Restricting the motion of a bird and a dog, even if drugs are used and/or they get used to it, is liable to cause discomfort and so I think is problematic on those grounds alone. It restricts their ability to future streams of pleasures of a varied and familiar kind. Certainly pain and pleasure are not the only issue here. Most of my friends in the US keep their cats inside, thinking, no doubt correctly, that they are safer not going out, but I tend to think that this interferes with the natural course of pleasures and pains that cats are in most cases entitled to enjoy. As for insects, I argued that if the case for them being conscious is not definitely settled one way or another, then we should assume they are conscious, and not gratuitously harm them. Flowers, by contrast, are fair game.

I think it's unnatural to describe the problem for the dog or bird (in my 5/21 examples) simply as missed happiness, but we can easily just block that explanation by supposing they are drugged into feeling no pain and feeling happy. I still see the severe restriction of the animals' lives as morally problematic. Many people do find it quite intuitive to say that such treatment is disrespectful, though there are other ways of describing what's going wrong (for example, in terms of capacities not being used or rights being violated). I grant, though, that for some philosophers all that matters ethically is maximizing pleasure and minimizing pain. That's certainly one venerable position.

I think there is a difference between saying that all that matters is pleasure and pain, and thinking that pleasure and pain is a good place to start when looking at such issues. If it is an open question whether ants feel pain, then we should not kill them, if that might hurt them, it seems to me. As has been suggested, perhaps there are other reasons not to kill them also, and these should be investigated, but there is something very clear about the pain issue which is not present in the other approaches to the topic.

I remember growing strawberries once and each strawberry had bites in it, from slugs and birds, and I thought at the time that this was OK. The slug had had a bit, the bird had had a bit, and I could, after a bit of paring, have a bit also. This would not work for a commercial strawberry grower, of course, but I do not feed my family through my skill as an agriculturist, fortunately, so why kill animals who might suffer in order to have perfect strawberries? This strikes me as the first question to ask, and the more sophisticated considerations that arise here are significant but lack the perspicacity of the pain issue.

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