Response to Stephen Hawking

September 5, 2001 by Ray Kurzweil

Stephen Hawking recently told the German magazine Focus that computers were evolving so rapidly that they would eventually outstrip the intelligence of humans. Professor Hawking went on to express the concern that eventually, computers with artificial intelligence could come to dominate the world. Ray Kurzweil replies.

Originally published September 5, 2001 on as a response to Stephen Hawking, whose sentiments can be read here.

Hawking’s recommendation is to (i) improve human intelligence with genetic engineering to “raise the complexity of … the DNA” and (ii) develop technologies that make possible “a direct connection between brain and computer, so that artificial brains contribute to human intelligence rather than opposing it.”

Hawking’s perception of the acceleration of nonbiological intelligence is essentially on target. It is not simply the exponential growth of computation and communication that is behind it, but also our mastery of human intelligence itself through the exponential advancement of brain reverse engineering.

Once our machines can master human powers of pattern recognition and cognition, they will be in a position to combine these human talents with inherent advantages that machines already possess: speed (contemporary electronic circuits are already 100 million times faster than the electrochemical circuits in our interneuronal connections), accuracy (a computer can remember billions of facts accurately, whereas we’re hard pressed to remember a handful of phone numbers), and, most importantly, the ability to instantly share knowledge.

However, Hawking’s recommendation to do genetic engineering on humans in order to keep pace with AI is unrealistic. He appears to be talking about genetic engineering through the birth cycle, which would be absurdly slow. By the time the first genetically engineered generation grows up, the era of beyond-human-level machines will be upon us.

Even if we were to apply genetic alterations to adult humans by introducing new genetic information via gene therapy techniques (not something we’ve yet mastered), it still won’t have a chance to keep biological intelligence in the lead. Genetic engineering (through either birth or adult gene therapy) is inherently DNA-based and a DNA-based brain is always going to be extremely slow and limited in capacity compared to the potential of an AI.

As I mentioned, electronics is already 100 million times faster than our electrochemical circuits; we have no quick downloading ports on our biological neurotransmitter levels, and so on. We could bioengineer smarter humans, but this approach will not begin to keep pace with the exponential pace of computers, particularly when brain reverse engineering is complete (within thirty years from now).

The human genome is 800 million bytes, but if we eliminate the redundancies (e.g., the sequence called “ALU” is repeated hundreds of thousands of times), we are left with only about 23 million bytes, less than Microsoft Word. The limited amount of information in the genome specifies stochastic wiring processes that enable the brain to be millions of times more complex than the genome which specifies it. The brain then uses self-organizing paradigms so that the greater complexity represented by the brain ends up representing meaningful information. However, the architecture of a DNA-specified brain is relatively fixed and involves cumbersome electrochemical processes. Although there are design improvements that could be made, there are profound limitations to the basic architecture that no amount of tinkering will address.

As far as Hawking’s second recommendation is concerned, namely direct connection between the brain and computers, I agree that this is both reasonable, desirable and inevitable. It’s been my recommendation for years. I describe a number of scenarios to accomplish this in my most recent book, The Age of Spiritual Machines, and in the book précis “The Singularity is Near.”

I recommend establishing the connection with noninvasive nanobots that communicate wirelessly with our neurons. As I discuss in the précis, the feasibility of communication between the electronic world and that of biological neurons has already been demonstrated. There are a number of advantages to extending human intelligence through the nanobot approach. They can be introduced noninvasively (i.e., without surgery). The connections will not be limited to one or a small number of positions in the brain. Rather, the nanobots can communicate with neurons (and with each other) in a highly distributed manner. They would be programmable, would all be on a wireless local area network, and would be on the web.

They would provide many new capabilities, such as full-immersion virtual reality involving all the senses. Most importantly, they will provide many trillions of new interneuronal connections as well as intimate links to nonbiological forms of cognition. Ultimately, our minds won’t need to stay so small, limited as they are today to a mere hundred trillion connections (extremely slow ones at that).

However, even this will only keep pace with the ongoing exponential growth of AI for a couple of additional decades (to around mid-twenty-first century). As Hans Moravec has pointed out, ultimately a hybrid biological-nonbiological brain will ultimately be 99.999…% nonbiological, so the biological portion becomes pretty trivial.

We should keep in mind, though, that all of this exponentially advancing intelligence is derivative of biological human intelligence, derived ultimately from the thinking reflected in our technology designs, as well as the design of our own thinking. So it’s the human-technology civilization taking the next step in evolution. I don’t agree with Hawking that “strong AI” is a fate to be avoided. I do believe that we have the ability to shape this destiny to reflect our human values, if only we could achieve a consensus on what those are.