# Ken Steiglitz: Garage Rock and the Unknowable

Here is the second post in a series by The Discrete Charm of the Machine author Ken Steiglitz. You can access the first post here

I sat down to draft The Discrete Charm of the Machine with the goal of explaining, without math, how we arrived at today’s digital world. It is a quasi-chronological story; I take what I need, when I need it, from the space of ideas. I start at the simplest point, describing why noise is a constant threat to information and how using discrete values (usually zeros and ones) affords protection and a permanence not possible with information in analog (continuous) form. From there I sketch the important ideas of digital signal processing (for sound and pictures), coding theory (for nearly error-free communication), complexity theory (for computation), and so on—a fine arc, I think, from the boomy and very analog console radios of my childhood to my elegant little internet radio.

Yet the path through the book is not quite so breezy and trouble-free. In the final three chapters we encounter three mysteries, each progressively more fundamental and thorny. I hope your curiosity and sense of wonder will be piqued; there are ample references to further reading. Here are the problems in a nutshell:

1. Is it no harder to find a solution to a problem than to merely check a solution? (Does P = NP?) This question comes up in studying the relative difficulty of solving problems with a computing machine. It is a mathematical question, and is still unresolved after almost 40 years of attack by computer scientists.
As I discuss in the book, there are plenty of reasons to believe that P is not equal to NP and most computer scientists come down on that side. But … no one knows for sure.
2. Are the digital computers we use today as powerful—in a practical sense—as any we can build in this universe (the extended Church-Turing thesis)? This is a physics question, and for that reason is fundamentally different from the P=NP question. Its answer depends on how the universe works.
The thesis is intimately tied to the problem of building machines that are essentially more powerful than today’s digital computers—the human brain is one popular candidate. The question runs deep: some believe there is magic to found beyond the world of zeros and ones.
3. Can a machine be conscious? Philosopher David Chalmers calls this the hard problem, and considers it “the biggest mystery.” It is not a question of mathematics, nor of physics, but of philosophy and cognitive science.

I want to emphasize that this is not merely the modern equivalent of asking how many angels could dance on the point of a pin. The answer has most serious consequences for us humans: it determines how we should treat our android creations, the inevitable products of our present rush to artificial intelligence. If machines are capable of suffering we have a moral responsibility to treat them compassionately.

My first reaction to the third question is that it is unanswerable. How can we know about the subjective mental life of anyone (or any thing) but ourselves? Philosopher Owen Flanagan called those who take this position mysterians, after the proto-punk band ? and the Mysterians. Michael Shermer joins this camp in his Scientific American column of July 1, 2018. I discuss the difficulty in the final chapter and remain agnostic—although I am hard-pressed even to imagine what form an answer would take.

I suggest, however, a pragmatic way around the big third question: Rather than risk harm, give the machines the benefit of the doubt. It is after all what we do for our fellow humans.

Ken Steiglitz is professor emeritus of computer science and senior scholar at Princeton University. His books include The Discrete Charm of the MachineCombinatorial OptimizationA Digital Signal Processing Primer, and Snipers, Shills, and Sharks. He lives in Princeton, New Jersey.

This post is part of a series, explore additional posts here<< Ken Steiglitz: When Caruso’s Voice Became ImmortalKen Steiglitz: It’s the Number of Zeroes that Counts >>