# Why shouldn't invertebrates feel pain **URL:** \ **Category:** Great Debates\ **Created:** [May 22, 2006, 7:30am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723 "2006-05-22T07:30:00Z")\ **Posts on this page:** 13\ **Page:** 3
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [May 24, 2006, 3:02am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/41 "2006-05-24T03:02:50Z")
> [@Der Trihs](#): > > I’ve read that an eating wasp can have it’s abdomen cut off and it’ll just keep eating; that’s an example of how uncoordinated their nervous systems are. Yeah, and such things can even go on in more complex creatures. I once saw a program about lions in which the lions killed a gazelle. While the lions were tearing away the rear end, the gazelle was still eating grass. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [May 24, 2006, 3:42am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/42 "2006-05-24T03:42:31Z")
> [@David Simmons](#): > > Yeah, and such things can even go on in more complex creatures. I once saw a program about lions in which the lions killed a gazelle. While the lions were tearing away the rear end, the gazelle was still eating grass. Which leads to another question : Do all _vertebrates_ feel pain the way we do ? More, less ? I recall an example used on this subject; a pair of male rhesus monkeys fought; the winner had one of his testicles bitten off. The next day, he was having sex. Did he feel the kind of pain we would ? ---
**Author:** ![Strinka](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/strinka/32/512_2.png) [@Strinka](https://boards.straightdope.com/u/Strinka)\ **Post date:** [May 24, 2006, 3:43am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/43 "2006-05-24T03:43:00Z")
What is “pain”? How does it differ from a reaction to a harmful stimulus? Maybe it seems like a stupid question, but I think it needs to be addressed in a debate about whether or not certain animals feel pain. ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [May 24, 2006, 4:43am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/44 "2006-05-24T04:43:45Z")
> [@Der Trihs](#): > > I recall an example used on this subject; a pair of male rhesus monkeys fought; the winner had one of his testicles bitten off. The next day, he was having sex. Did he feel the kind of pain we would ? Heck, that wouldn’t stop most guys I know from having sex. 🙂 ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 24, 2006, 7:35am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/45 "2006-05-24T07:35:05Z")
> [@Der Trihs](#): > > Not necessarily; IIRC robots designed to imitate that sort of distributed processing manage with zero central control. The gaits emerge spontaneously, and aren’t programmed into the machines. Of course that doesn’t prove insects do that, but it shows it’s possible. > > Note that your linked article makes many references to sensory input; that’s how such robots work. They react to the input of many sensors, not to any central control. It also points out how the legs are controlled by nerve clusters in the leg, not outside nerves. Sure, but the apparently coordinated gait must emerge due to _some kind of intercommunication/feedback_ between the local controllers, otherwise, why should it emerge at all? Coordination requires some kind of communication; not necessarily _top down_ from a central controller; networked intercommunication and sensor feedback might suffice, but then the individual elements cannot be said to be working in entire isolation. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [May 24, 2006, 8:00am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/46 "2006-05-24T08:00:34Z")
> [@Mangetout](#): > > Sure, but the apparently coordinated gait must emerge due to _some kind of intercommunication/feedback_ between the local controllers, otherwise, why should it emerge at all? Interaction with the environment and senses. Internal communication isn’t necessary for two sets of reflexes to mesh. There are even examples in humans, such as people with surgically split brains who still coordinate their actions. Or the cojoined twin girls I read about a while ago, who are basically 2 heads on 1 body; each head controls only half the body, yet they can still walk and even play musical instruments. Yes, they’re human, but those are reflexes and not intelligence at work. Lesson : Reflexes can have no connection to one another, yet act in concert. We tend to think otherwise, because that’s not usually how we design things. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 24, 2006, 8:17am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/47 "2006-05-24T08:17:54Z")
I don’t see that it makes a whole lot of difference, conceptually; communication is communication, whether it takes place across your own nervous system, or utilises external methods - it’s all just physics in the end - and I think we would be limiting ourselves, philosophically, if we were to insist that the totality of processes that constitute a sense of awareness must be exclusively inbuilt. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 24, 2006, 8:21am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/48 "2006-05-24T08:21:58Z")
> [@Der Trihs](#): > > Lesson : Reflexes can have no connection to one another, yet act in concert. We tend to think otherwise, because that’s not usually how we design things. In Fact, I’m going to argue this one: no, **by definition** , they cannot (except by pure coincidence) act in concert if they have **no connection** to each other. Do you mean no _inbuilt_ connection to one another? ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [May 24, 2006, 8:51am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/49 "2006-05-24T08:51:56Z")
> [@Mangetout](#): > > Do you mean no _inbuilt_ connection to one another? Yes. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 24, 2006, 9:02am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/50 "2006-05-24T09:02:15Z")
Fair enough. Conceptually, I don’t have a problem with the notion of awareness arising in an organised system that utilises non-inbuilt communication paths as part of its operation. I would not be so bold as to suggest any such system exists on our planet, but I don’t regard it as an impossibility. ---
**Author:** ![tmcinroy](https://avatars.discourse-cdn.com/v4/letter/t/51bf81/32.png) [@tmcinroy](https://boards.straightdope.com/u/tmcinroy)\ **Post date:** [May 26, 2006, 12:44am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/51 "2006-05-26T00:44:04Z")
There is some discussion of this topic in Temple Grandin’s book “Animals In Translation”. The most relevent point is that insects will attempt to walk on a damaged leg, and so we can assume that they lack pain. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 26, 2006, 8:04am UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/52 "2006-05-26T08:04:31Z")
> [@tmcinroy](#): > > The most relevent point is that insects will attempt to walk on a damaged leg, and so we can assume that they lack pain. That doesn’t seem like a particularly sound piece of reasoning to me; is it not the case that some vertebrates will still try to use a damaged body part? ---
**Author:** ![bup](https://avatars.discourse-cdn.com/v4/letter/b/6bbea6/32.png) [@bup](https://boards.straightdope.com/u/bup)\ **Post date:** [May 26, 2006, 7:24pm UTC](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723/53 "2006-05-26T19:24:09Z")
> [@tmcinroy](#): > > There is some discussion of this topic in Temple Grandin’s book “Animals In Translation”. The most relevent point is that insects will attempt to walk on a damaged leg, and so we can assume that they lack pain. Yeah, they do, and some of the arguments I’ve seen that they don’t experience pain are because they still act “normally” in mortal peril. You can’t accept that as proof of ‘non-pain’ any more than you can accept apparent struggling and distress as proof of ‘pain.’ Anybody who says they know for sure one way or the other is bullshitting. [Previous page](https://boards.straightdope.com/t/why-shouldnt-invertebrates-feel-pain/357723.md?page=2)