what do you guys think about plants that eat animals like the venus fly trap? they're not sentient but the flys and stuff they eat are

I think flies are negligibly sentient. I'd be more worried about animals that eat smarter animals, like pigs.

Also, I don't think the sentience of a predator is significant compared to its effect on the pray.

i used to have one and the flys seemed very sentient when it was closing on them.

as reagrds the second part of your post what do you mean exactly?

First part: read Sentience and Brain size.

Second, I mean that if you have a predator that creates one utilon by existing, and destroys 100 by eating, it has a net utility of -99 utilons. If you have a similar predator that isn't sentient, it has a net utility of -100 utilons. How much does a 1% difference matter? You should try to kill both of them.

Also, come to think of it, most diseases are such predators.

Yeah, I think it's true. A venus fly trap is causing suffering by eating sentient beings. So are humans. Neither of these is a good thing. The main difference is that humans can, at least in theory, change their mind about the ethics of eating. So it's the humans, especially the open-minded ones, who deserve the focus of our attention.

Okay this is weird that I've just seen this because today I encouraged the girl I look after (I'm a nanny) to buy a venus flytrap and then panicked lol.

I encouraged her to buy it because it was from Oxfam. Then I worried about the extra flies that would experience painful deaths because of my action. Then I realised that the flies would probably have had painful deaths anyway. Then we agreed that she should squish some flies quickly and feed them to her plant. Then we said she should squish some spiders too because they give flies very painful deaths.

I love that I can have such conversations with an 8-year-old

jeez yea she must have awesome parents if you can talk to her about stuff like that!:D youll probably have to wriggle the fly around a little (maybe a very little) in the fly traps mouth and then let it go when it closes because it senses the movement and then shuts

"I think flies are negligibly sentient. I'd be more worried about animals that eat smarter animals, like pigs."

Either someone is sentient (they have subjective experience) or they don't. There are no degrees to sentience. Even if some animals feel emotional states less intensely in response to the same stimuli, have less accurate sensory perception or are cognitively less developed; you either experience subjective mental states or you don't. Either someone can see or they can't see. Less accurate vision doesn't mean one can see less, although some animals do have a wider range of vision. The only negligible amount of pain (if happiness and pain are the mental states you care about) is 0. The mildest amount of happiness or pain is still good or bad, it's just not as good or bad as more intense (or prolonged) happiness or pain. Either flies can experience some amount of pain or they can't and that wouldn't be directly related to how cognitively developed they are. Many non-human animals have sharper senses or senses that we lack despite being cognitively less developed. Humans who are more cognitively developed don't experience pain more intensely than humans who are less so. Humans don't have the largest brains, even relative to our size.

"Also, I don't think the sentience of a predator is significant compared to its effect on the pray."

I agree (if I understand you right). I don't have a problem with eliminating all venus fly traps or bacteria or viruses that cause illness (in sentient animals) if doing so doesn't indirectly disadvantage sentient beings. I have a 'problem' with eliminating sentient predators even when it's justified.

" Then I realised that the flies would probably have had painful deaths anyway. "

I don't know how many flies benefit more, overall, from their lives than they are harmed by them but I'm sure they experience some happiness when eating and mating and maybe even from other things like flying, basking in the sun or warm light, finding certain smells or things to be interesting or just enjoying the moment (I admit I'm being very speculative with the last two and maybe flying). I remember reading an article that claimed that fruit flies who weren't able to mate were more likely to indulge in alcohol.