A startup is building computer chips using real neurons

We are all machines. The idea that one type of machine or another cannot feel "pain" is simply a rationalization for human behavior that causes harm to other organisms, like hunting and fishing and killing wasps.

Pain is a sensation that drives an animal to quickly react to injurious situations. Consider a robot made with Brooks's subsumption architecture [1]. The basal level of behavior drive of the robot is its self-preservation. That level of behavior drive can halt all the higher-order behaviors to monopolize processing and locomotion. Imagine that this behavior drive is triggered when the ambient temperature approaches a level that can damage the battery, and attempts to move the robot to the lowest-temperature zone available. That is functionally no different than what happens to a person in a house fire.

All we have done with the word "pain" is to set up an arbitrary delineation based on the hormonal/neuronal response that links our sensory apparatus to our behavioral drive.

[1] https://people.csail.mit.edu/brooks/papers/representation.pd...

I agree with you, pain is a useful signal or it could be a systemic damage that wrongly sends these signals. However, when we, humans, refer to pain we clump all the unpleasant things we experience together. One such pain is the emotional /psychological pain and this type of pain is more likely to occur in such a system without a body. This is also a signal/state and is also useful to delineate it from another state. If such system is to experience joy it better know what pain is or otherwise wouldn't be able to delineate.

In this case, the complexity is in how you define the word 'suffering'. Is a worm suffering when it tries to escape from a heat source? Is a human infant suffering when it cries in response to a needle prick? Is a motor driver suffering when it raises a high-temperature alarm? As far as I can see they're all on the same continuum, and it's possible to find people who will answer either way to any of the above.

Careful, or you might use a definition of pain too broad to be useful.

Plants, single-celled organisms, thermostats, and anti-lock braking systems meet your use of the word.

Almost all of us know what it means to be in pain. It’s the hard to put into words subjective experience of suffering that is worth making ethical decisions about, not the autonomous reflex that doesn’t come with conciousness-is-a-poor-word-but-I-lack-a-better-alternative.

The experience of reality happens on an individual level. It sounds self evident. The corollary is that the feelings you feel are yours and yours alone to feel.

When we use language to describe our experience - pain, joy, loss, fear - we don't transfer the experience proper. What we share is an expression of our experience.

If you describe your current experience as "joy", then you arrive at that expression because - arguably - you learned that concept from your parents as a toddler. I say "arguably" because this is where the "nature vs nurture" debate kicks in. I'm not going to delve into that can of worms.

Suffice to say that we can't transfer our exact experience to another individual; but that we can express our experience and that others are able to interpret that expression. And that a shared understanding comes from a shared conceptual frame of reference.

Art is a great way to challenge that shared frame of reference. Understanding art implies trying to interpret what an artist is expressing. Sometimes the artist doesn't intend to express their own experience, but rather evoke a particular experience or even contradicting experiences within the audience. That's why some art throws us from our feet.

But this isn't about art. This is about suffering. That's where concepts such as empathy and compassion come into play. Those concepts refer not to the actual experience of suffering proper within individuals, but rather the capacity to recognize the experience of suffering in others through their expressions. If you see someone express grief through crying, apathy, irritation,... then empathy means that you understand that they are experiencing grief and you are able to also have that same experience behind the expression as an individual, independent of what others are feeling.

Empathy, compassion and a shared understanding work best if there's a close resemblance between you and the other. Hence why there's little doubt about the experiences of family, close friends and so on. It starts to become harder when you think about suffering in the context of people with different cultures and languages whom you've never met and who live on the other side of the globe. Animals? There's another level that increases that distance. Sure, your pet may be expressing their experience, but how do you know you're not projecting?

And so, here we are, considering neural networks and neurons attached to breadboards. Do they have a similar experience of reality? Do they experiencing suffering in a way that matches with what humans conceptually and "broadly" understand as "suffering"? It's not like we can ask, and even if we could, how would we possibly be able to interpret the expression of "suffering" they convey to us?

For instance, up until the 1970's, infants up until 15 months simply didn't receive anesthesia for surgeries. Everyone assumed that they didn't feel pain because the shared frame of reference among medical practitioners didn't allow for the interpretation of their expression as "oh, they are in pain".

https://www.nytimes.com/1987/12/17/opinion/l-why-infant-surg...

And so, one argument could be that we are already torturing neural networks and we aren't even aware we're doing it because we simply lack a common frame of reference to pick up the expressions of an experience of pain. Hence the cautious reluctance to sanction free experimentation that unwittingly may elicit the experience of suffering.