Creativity is an acid test for AI and cognitive science. If computers cannot be creative, then (a) they cannot be intelligent, and (b) people are not machines. However, the standard arguments against machine intelligence are not convincing.

Issues in computers and creativity include: Can computers be creative? Can they help us understand human creativity? How can they best enhance human creativity? What would the implications be for AI and cognitive science if computers could not be creative? This entry limits itself to two initial questions: Why is creativity important for AI and cognitive science? and How convincing are the standard arguments against machine creativity?
Since the French Enlightenment there has been a growing belief that people are machines, and today this belief is so deeply rooted in our culture that it is difficult to imagine what else people might be. But there is also a perception that computers cannot be creative. Lady Lovelace said that computers "have no pretensions to originate anything". This, too, has taken root in our culture, so that we tend to believe that people are machines, but also that machines cannot do something which is characteristically human.
There are in fact two intuitions here. If machines cannot be creative, then (a) they cannot be intelligent, and (b) people (who can be creative) cannot be machines. The first intuition concerns AI, and the second concerns cognitive science. If machines cannot be creative, then they cannot have "minds of their own", in the sense of being able to generate their own ideas, and it is difficult to see how a system that cannot generate its own ideas can be intelligent. This would be the end of AI's aspirations to develop intelligent machines. Equally, if machines cannot be creative, this would be the end of the French Enlightenment vision of Man as a Machine. This would deal a body blow to cognitive science, which tries to provide computational simulations of human cognitive processes. Of course, if creativity is not a computational process, it might still be possible to simulate it computationally. But if machines cannot be creative, the driving force behind cognitive science will have been lost, for cognitive science is driven by the beliefs that it is cognitive processes that matter, and that these can be performed by silicon computers as well as by carbon brains.
Consequently, creativity emerges as a key issue for AI and cognitive science - so how compelling are the arguments against machine creativity?
The case against computational creativity
The claim that computers cannot be creative turns out to be a cluster of related claims. A common version is that they cannot be creative because they merely follow instructions. But sometimes we instruct people to be creative. Pope Julius II instructed Michaelangelo to be creative when he painted the Sistine Chapel ceiling. So it is possible both to be creative and to be following instructions.
The reply to this will probably be that Julius only gave Michaelangelo very general instructions, and left the rest to him, whereas every single thing that a computer does is something that it was told to do. But in fact we do not instruct computers in every action that they perform. This would require us to give them millions of instructions per second.
The reply may now be that everything that they do follows from instructions that we give them. But what does this mean? If it means that the machine's performance literally follows from its instructions then it is false, for if we wrote all the instructions on a piece of paper, nothing at all would happen. Presumably it means that computers are designed to respond in a predictable way to their instructions. But even this isn't clear. Does it mean that computers are predictable, in the sense that we can predict their output given their input plus an exhaustive account of their innards? Or does it mean that we have designed the innards, so that the creativity is really ours?
Consider the second interpretation first. We can 'give someone a good education', but it is still their education. We can 'teach them to think for themselves', but they can still think for themselves. We can 'give someone a good mind' and (as we say) 'give them a mind of their own'. Haugeland (1985: 10) asks, "Why should an entity's potential for inventiveness be determined by its ancestry (like some hereditary title) and not by its own manifest competence?" If we discovered that we were created, it would not follow that we cannot be creative.
What about the other interpretation, that computers are predictable input-output devices? Well, why shouldn't creativity be predictable? Julius II could have predicted that Michaelangelo would creatively paint the Sistine Chapel ceiling.
The objection to this will probably be that he could only have predicted that Michaelangelo would be creative, not what he would create.
Here we need Margaret Boden's (1990/92) distinction between psychological creativity (P-creativity) and historical creativity (H-creativity). Something is P-creative if it is fundamentally novel for the individual, whereas it is H-creative if it is fundamentally novel with respect to the whole of human history.
We can predict P-creativity. For instance, we can put a child into an environment in which we know that she will discover something, or solve a problem, in a P-creative way.
What about H-creativity? We can predict that someone will be H-creative: we lock a genius in a cupboard and tell them that they can't come out until they have been H-creative. We cannot, it is true, predict what they will H-create--but let us be clear why we cannot do this. We cannot do it because then, in a sense, we would have created it first. It is not that we cannot predict what they will come up with. It is just that, by definition, H-creative thoughts cannot have been thought before, so that if you have the thought before Sally, then her thought isn't H-creative.
Notice, too, that the claim that we are considering is that something cannot be creative if it is predictable in principle. However, something can be predictable in principle without having been predicted in fact. If it was not predicted in fact then it may be fundamentally new with respect to human history. Consequently, something can be H-creative and predictable in principle.
Suppose we discovered that Michaelangelo was an intelligent machine built by a Renaissance genius called 'Michaelangelo'--or, to avoid confusion, just 'Mike'. And suppose Mike knew all that there was to know about Michaelangelo's innards, so that, in principle, he could predict the output for any given input. He did not, however, bother to make the predictions (he was too busy converting lead into gold). "Oh, very nice," he said, when he looked at the Sistine Chapel ceiling, and added, sotto voce, "Be careful what you say to the Pope."
The fact that Mike gave Michaelangelo his ability does not detract from Michaelangelo having the ability. And it doesn't detract from the qualities of the Sistine Chapel ceiling (always assuming that Mike gave Michaelangelo the right sorts of innards--not random ones, for instance). Finally, because Mike hadn't in fact predicted what the outcome would be, Michaelangelo's work was H-creative. It was fundamentally new with respect to human history.
It would seem, then, that the standard arguments against machine creativity are not convincing. But this does not close the account.
Terry Dartnall