Quote:
Originally Posted by whswhs
I don't know the source material; I haven't seen the film in question. So I can't really give an informed answer.
My basic view is that the Searle Chinese room argument, and the Turing test, are invalid as statements of what it is to be "human." They seem to focus entirely on language. I don't think that typed or written or even spoken inputs and outputs are sufficient for humanity or for sapience.
Consider the Turing machine. Can I say to it, "How did you like the chicken masala we had for dinner?" or "doesn't that singer have a great voice?" or "beautiful weather, isn't it?" Can it comment on the color of my eyes, or whether the room is too hot or too cold? A human being, if not disabled in specific ways, would be able to perceive and think about a vast range of things of that sort, and discuss them, without having been prepared to do so in advance; the discussion would be based on their awareness of the world and of their existence in it, their embodiment, and their language would be a way of expressing and focusing that awareness. For example, C can say to me, "He wants your attention," and I can look around and see that our cat has come up to where I'm sitting and flopped onto his back on the floor next to me—and a purely symbol manipulating engine, even if it could notionally pass the Turing test or do the Searle trick, could not do such things. (Setting aside the idea that its inputs come from a simulated human body in a simulated physical world.)
In other words, as a human being, and more broadly a sapient one, I have intentionality: I can direct my awareness to physical entities, and use language to refer to them. My language is not just a self-contained system of symbols: It contains words that refer to the world, such as "I," "you," "they," "here," "there," "now," "then," and "thus," and such words can guide another person's attention to a common feature of the environment. This is a big part of the primary use of language, which is face to face communication. Exchanging messages over the Internet, or by teletype, as Turing imagined, is a specialized secondary use of language.
And I can tell that another person, or a nonhuman animal without speech, is conscious by seeing them move their body in a way that directs their attention to stimuli that provide interesting information. Which also points at the kind of things I would take as providing evidence that a machine was conscious.
I hope this is some help.
|
Quote:
Originally Posted by whswhs
Well, on one hand, the brain does things that cannot be reduced to computation, too. It's an important source of chemical substances that influence human physiology and behavior, and it has intimate relations with the pituitary, which is the central performer in the human endocrine system.
It also outputs electrical signals to the muscles and such that don't take a binary on/off form. In fact no neurons do binary on/off; they do pulses with different frequencies. Of course you can model this mathematically, but then you can model the stresses and flows in the Earth's crust mathematically, and that doesn't mean that the Earth is a huge computer; it means that mathematics is science's characteristic tool.
I also think that talking about the relationship between the mind and the brain is a misleading phrasing. It's like talking about the relationship between the legs and running, as if running were a separate entity that somehow entered into an interaction with the legs.
|
The assumption that synaptic firing is the basic unit of mental function is not needed for a full simulation. By the way, we already know that it’s not the basic unit.
It’s not a real issue as we could simulate a brain on further levels, for example simulating every atom or every subatomic particle. It becomes just a problem of increased data size and complexity.
However: every physical aspect of the brain can be measured, and the sequence of its physical states and transformation can be reduced to an algorithm. In this level of reasoning, there is no world and the vision. There are physical alterations of specialised nerve cells hit by radiations, which in turn trigger a complex set of physical transformation in the brain. All of this can be simulated by a sequencer of physical states using a set of transformation rules (for example a computer).
The input is raw data with an appropriate format. It can be a simulation from another computer, or a sensor interfacing with the environment. As living beings we use a sensor (the eye); hopefully we’ll be soon able to build prostethic eyes/sensors for people with damaged eyes.
On the other hand, there are phenomena that we cannot simulate with a formal system. They are in two categories.
One is introspection or sentiency. As a qualitative phenomenon, it cannot be represented as formal system.
The second are undecidable propositions; we can manage them, but a formal system cannot.
The first is not a problem for the simulation. We never directly perceive the others’ experience of self; we just perceive their behaviours and we assume that they have self-awareness as we have*. In fact, if reality would be just a simulation feed to our brain, we could not tell the difference.
The second problem should be solved by the simulation use. Of course a computer simulating a mind would not have self-awareness or understanding of undecidable propositions, but it could behave like it had, and we couldn’t tell the diiference - as above.
*Regardless of speech. When my dog behaves happy, I perceive only her behaviour, and yet I assume that she is behaving happy because she
feels happy. I know that she is happy because I have first-hand experience of feeling and happyness in myself, and so she has and knows. Even more amazing, this implies that we know the other one knows our feelings because it is like us.
PS: Sometimes I think that this board has the most stimulating discussions and the most brilliant minds in the whole internet. Thanks guys!