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tags: Computers Science
rel: ELIZA Reinterpreted
John McCarthy is critical of Weizenbaum’s points
Summary
Summary of W’s points:
- Weizenbaum doesn’t name any specific task that computers cannot carry out, because he wishes “to avoid the unnecessary, interminable, and ultimately sterile exercise of making a catalogue of what computers will and will not be able to do, either here and now or ever”. It is also stated that human and machine reasoning are incomparable and that the sensory experience of a human is essential for human reasoning.
- There are tasks that computers should not be programmed to do. Weizenbaum also objects to computer hookups to animal brains and computer conducted psychiatric interviews.
- Science has led people to a wrong view of the world and of life.
- Science is not the sole or main source of reliable general knowledge. He doesn’t propose any other sources of knowledge or say what the limits of scientific knowledge is except to characterize certain thoughts as “obscene.”
Eliza
Perhaps the most interesting part of the book is the account of his own program ELIZA that parodies Rogerian non-directive psychotherapy and his anecdotal account of how some people ascribe intelligence and personality to it. In my opinion, it is quite natural for people who don’t understand the notion of algorithm to imagine that a computer computes analogously to the way a human reasons.
Weizenbaum in his Eliza paper states:
“One goal for an augmented ELIZA program is thus a system which already has access to a store of information about some aspect of the real world and which, by means of conversational interaction with people, can reveal both what it knows, i.e. behave as an information retrieval system, and where its knowledge ends and needs to be augmented. Hopefully the augmentation of its knowledge will also be a direct consequence of its conversational experience. It is precisely the prospect that such a program will converse with many people and learn something from each of them which leads to the hope that it will prove an interesting and even useful conversational partner.”
On Computers he says
- since a computer cannot have an experience of man, it cannot understand man.
- since the problem hasn’t been solved in 20 years (at time of writing) it is time to give up.
- the book confuses computer simulation of a phenomenon with its formalization in logic. A sim is only one kind of formalization and it is not often the most useful, even to a computer. Good parts
- what would it mean for a computer to hope or be desperate for love?
The Chomsky school may be embarassed by the fact that it has only recently arrived at the conclusion that the semantics of natural language is more fundamental than its syntax, while AI based researchers have been pursuing this line for fifteen year.
Polemical Sins: Dehumanizing effect of the invention of the clock:
“The clock had created literally a new reality; and that is what I meant when I said earlier that the trick man turned that prepared the scene for the rise of modern science was nothing less than the transformation of nature and of his perception of reality. It is important to realize that this newly created reality was and remains an impoverished version of the older one, for it rests on a rejection of those direct experiences that formed the basis for, and indeed constituted the old reality. The feeling of hunger was rejected as a stimulus for eating; instead one ate when an abstract model had achieved a certain state, i.e. when the hand of a clock pointed to certain marks on the clock’s face (the anthropomorphism here is highly significant too), and similarly for signals for sleep and rising, and so on.”