I haven't kept up with this thread. But I wanted to counter the idea of a simple ordering of painfulness.
A simple ordering of painfulness is one way to think about pain that might work in some simple systems, where resources are allocated in a serial fashion, but may not work in systems where resource allocation choices are not necessarily serial and mutually exclusive. If our system has a heterarchy of goal-accomplishing resources--some of which imply others and some of which exclude others, the problem of simple orderings of painfulness may be not useful for thinking about these types of resource allocation. -- Bo On Sat, 16 Jun 2007, Matt Mahoney wrote: ) ) --- Jiri Jelinek <[EMAIL PROTECTED]> wrote: ) ) > Eric, ) > ) > I'm not 100% sure if someone/something else than me feels pain, but ) > considerable similarities between my and other humans ) > ) > - architecture ) > - [triggers of] internal and external pain related responses ) > - independent descriptions of subjective pain perceptions which ) > correspond in certain ways with the internal body responses ) > ) > make me think it's more likely than not that other humans feel pain ) > the way I do. ) ) There is a simple proof for the existence of pain. Define pain as a signal ) that an intelligent system has the goal of avoiding. By the equivalence: ) ) (P => Q) = (not Q => not P) ) ) if you didn't believe the pain was real, you would not try to avoid it. ) ) (OK, that is "proof by belief". I omitted the step (you believe X => X is ) true). If you believe it is true, that is good enough). ) ) > The further you move from human like architecture the less you see the ) > signs of pain related behavior (e.g. the avoidance behavior). Insect ) > keeps trying to use badly injured body parts the same way as if they ) > weren't injured and (unlike in mammals) its internal responses to the ) > injury don't suggest that anything crazy is going on with them. And ) > when I look at software, I cannot find a good reason for believing it ) > can be in pain. The fact that we can use pain killers (and other ) > techniques) to get rid of pain and still remain complex systems ) > capable of general problem solving suggests that the pain quale takes ) > more than complex problem solving algorithms we are writing for our ) > AGI. ) ) Pain is clearly measurable. It obeys a strict ordering. If you prefer ) penalty A to B and B to C, then you will prefer A to C. You can estimate, ) e.g. that B is twice as painful as A and choose A twice vs. B once. In AIXI, ) the reinforcement signal is a numeric quantity. ) ) But how should pain be measured? ) ) Pain results in a change in the behavior of an intelligent system. If a ) system responds Y = f(X) to input X, followed by negative reinforcement, then ) the function f is changed to output Y with lower probability given input X. ) The magnitude of this change is measurable in bits. Let f be the function ) prior to negative reinforcement and f' be the function afterwards. Then ) define ) ) dK(f) = K(f'|f) = K(f, f') - K(f) ) ) where K() is algorithmic complexity. Then dK(f) is the number of bits needed ) to describe the change from f to f'. ) ) Arguments for: ) - Greater pain results in a greater change in behavior (consistent with animal ) experiments). ) - Greater intelligence implies greater possible pain (consistent with the ) belief that people feel more pain than insects or machines). ) ) Argument against: ) - dK makes no distinction between negative and positive reinforcement, or ) neutral methods such as supervised learning or classical conditioning. ) ) I don't know how to address this argument. Earlier I posted a program that ) simulates a programmable logic gate that you train using reinforcement ) learning. Note that you can achieve the same state using either positive or ) negative reinforcement, or by a neutral method such as setting the weights ) directly. ) ) -- Matt Mahoney ) ) ) -- Matt Mahoney, [EMAIL PROTECTED] ) ) ----- ) This list is sponsored by AGIRI: http://www.agiri.org/email ) To unsubscribe or change your options, please go to: ) http://v2.listbox.com/member/?&; ) ----- This list is sponsored by AGIRI: http://www.agiri.org/email To unsubscribe or change your options, please go to: http://v2.listbox.com/member/?member_id=231415&user_secret=e9e40a7e
