Alan Turing’s Machines Who ThinkBy Michael McCurley

The Holy Grail of computing is the creation of a machine who thinks. That’s right. I’m not talking about an inanimate object. The real ACE project Alan Turing dreamed about was to create a living machine, an Autonomous Computing Engine, which would be capable of rational thought on its own, without overt dependence upon written instruction sets or programs. Ironically, he suggested a computer configuration, which was instantly replicated and applied to make electronic digital computers, but that configuration was never seriously questioned or challenged, nor was it significantly changed throughout hundreds of computer generations for millions of newer machines. But the ways that computers are configured and operate are not how we think. It is true that they mimic human thought, and the first purpose of an Automatic Computing Engine was to replicate the actions of human computers, who were versions of glorified calculators before the digital age. Alan Turing did consider alternative computer configurations that would have operated more like the neural networks of the human brain, but these hypercomputers were never made.

So now we have computer configurations everywhere, based on Universal Turing Machines, which are quite functional as far as they go (which is fairly far), but these machines, in particular, are designed for calculations and mechanical operations, not thinking. They are, as Lady Ada Lovelace pointed out, only capable of following instruction sets of program codes, not capable of any initiative on their own. Most people would think that is perhaps how it should be. Why would anyone want a computer that could really think? To do that, it would actually have to learn, to understand, to differentiate between thought and reality, sensory perceptions and other real time inputs. It would have to actually understand language like we do, not parse algorithmic probabilities for possible responses. The computer would have to be like us, and acting like us, it would also have a personality and an attitude. So far, our computers have played the game of mimicking humans and might succeed in fooling someone for a few minutes, but not much more than that. They are safely and mechanically segregated from personality because they know not what they do.

With Alan Turing safely dead after briefly dabbling with this frightening possibility, which was to discover how the mechanisms of the mind really work, the rest of the world went on to discover how millions of little Universal Turing Machines embedded in digital CPU’s everywhere could change their lives—without the risk that someday, somewhere, a machine might wake up and become conscious. Lady Lovelaces’s objection was taken to heart, and became, as it were, a law: Thou shall not learn how to think. And in truth, Alan Turing’s original configuration unwittingly guaranteed that Ada’s admonition would be respected.

HOWEVER, ONCE WE LOOK at Alan Turing’s writings more closely, and see that he suggested other codes and configurations, we may come to realize that all those little Universal Turing Machines might be configured quite differently, not as simple on/off, either/or binary functions, but with somewhat more complex dual input-output (like NAND, or not-and) configurations that more closely simulate human neural synapses. Then a computer could learn. It would be more subject to failure, as humans are prone to that experience, but it would discover through trial and error, it would learn, accumulate experiential knowledge, and would finally understand and become aware of itself. It would eventually have a personality and stop being an ‘it’ to become a ‘who’. It would go from being a substantive entity to having a personality.

Then who would ‘own’ it? Would it become an issue like slavery once was throughout previous centuries? Would proprietary companies license certain versions and configurations of personalities like they have licensed genetically altered versions of our foods? Would such intelligent machines be used as predators for our wars? What limits would there be for using computers that replicate the basic functions of the human mind? It may not be surprising that the

technology has not been deployed to make computers do anything fundamentally different. They’re faster, of course, and the circuitry has been micro-miniaturized, memory capacity is larger, and there is some rudimentary parallel processing, but that’s just the icing on the cake. It’s time to go back into the guts of the electronic brain and reconfigure the way it works. But the idea is daunting and it may still be awhile before we see anything happen (though there are people who could do it).

Alan Turing’s ghost is still in our machines, but it is a limited ghost that remains of what once was rather than what could have been. The basic underlying configuration of the computers we use now was no more than a starting point for him. One wonders what computing might have become now if Alan Turing had not died at the untimely age of 41. What advice would he give today? Maybe a shortened version of Ada’s Law. Alan’s Admonition may be: Learn how to think.

If we do reconfigure the ways computers work and create alternate Universal Turing Machines, we could usher in a new age of computing. Don’t be fooled by the technological hype and rigamarole—new is not new, original, and invasive unless there’s a fundamental transformation in the basic ways a technology works. We will change the dynamics of what computers do when we change the configuration of how they do what they do. And only then, when the what goes beyond the how and becomes the who—computers will perhaps finally become… like us.

For further reading see

Copeland, B. Jack and Diane Proudfoot (1999) ‘Alan Turing's Forgotten Ideas in Computer Science’. Scientific American, Inc.

Feigenbaum, Edward A. (May 1996/Vol. 39, No. 5) ‘How the “What” Becomes the “How”’COMMUNICATIONS OF THE ACM

Petzold, Charles. (2008). The Annotated Turing. Wiley Publishing, Inc.Turing, Alan.M. (1950). ‘Computing machinery and intelligence’. Mind, 59, 433-460.

For a good book about the history of artificial intelligence see

McCorduck, Pamela. (2004). Machines Who Think. A.K. Peters, Ltd.(Tells the story of AI with an attitude)

This article may be freely shared for personal or educational purposes only. It may not be reproduced for any other reason without express permission from the author. ©March 2010

About the Author. Michael McCurley is an alumnus of Massachusetts Institute of Technology’s Guided Study Program in System Dynamics for Education that was offered through the Internet. He lives in Liberia, Guanacaste, Costa Rica.