Most of us will be familiar with Arthur Clarke’s famous observation about ships.
If man survives for as long as the least successful of the dinosaurs—those creatures whom we often deride as nature’s failures—then we may be certain of this: for all but a vanishingly brief instant near the dawn of history, the word ‘ship’ will mean— ‘spaceship.’
Spare a thought for computers. Today we mostly think of computers as electronic brains. But for nearly 2,000 years people computed using mechanical representations of the virtual things. Wikipedia reviews some of the history.
The astrolabe was invented in the Hellenistic world in either the 1st or 2nd centuries BC and is often attributed to Hipparchus. A combination of the planisphere and dioptra, the astrolabe was effectively an analog computer capable of working out several different kinds of problems in spherical astronomy. An astrolabe incorporating a mechanical calendar computer and gear-wheels was invented by Abi Bakr of Isfahan in 1235. Abū Rayhān al-Bīrūnī invented the first mechanical geared lunisolar calendar astrolabe, an early fixed-wired knowledge processing machine with a gear train and gear-wheels, circa 1000 AD.
Some of the older readers of the Belmont Club may have actually used mechanical computers themselves in the form of the Slide Rule. Collectors among you can obtain the K+E MODEL 4081-3, as used in Los Alamos to design the A-bomb. Here’s what Slide Rules looked like.
Until recently it was believed that only higher forms of life could invent computing devices, though that may depend on how you define a higher life form or a computing device.
I am most honoured to have the privilege to present the Foreword to this fascinating and wonderfully varied collection of contributions, concerning the nature of computation and of its deep connection with the operation of those basic laws, known or yet unknown, governing the universe in which we live. Fundamentally deep questions are indeed being grappled with here, and the fact that we find so many different viewpoints is something to be expected, since, in truth, we know little about the foundational nature and origins of these basic laws, despite the immense precision that we so often find revealed in them …
Even if all of this is accepted, we may still ask what would be the use of a little bit of non-computable action, from time to time, for the operation of the brain? … How far outside the normal scheme of computational physics would these hypercomputational actions be?
Penrose’s answer to his own question is worth reading the article for in itself. But none of these concerned the Navy men of World War 2. They had a problem to solve, which was then how to hit an enemy battleship, or airplane, maneuvering at considerable speed over distances of miles. And since they had no electronic circuitry to help them, they solved the problem as men had done for centuries previous. They solved it with precisely machined things.
It is almost a retro experience to hear the film narrator say, “a computer cannot do this without men”. We are used to thinking that computers can do stuff without us. But back in the day men to crank in the inputs. More importantly they had to decide which things to point the 16 inch guns at. For an Iowa Class battleship could sink a US destroyer about as easily as a Japanese destroyer. So men. Those things were taken for granted in those days. We can almost hear Penrose whispering in the background asking, “are there decisions the computer cannot make?”
The old World War 2 guys knew there were some things we had to tell the computer. Today we have gone far beyond the gears, working surfaces and differentials of the 1940s. Compared to it the NSA is a wonder, as far from primitive fire control as a Greek god might be from the amoeba. Yet perhaps we may still need men to decide “at what do we point this vast machine at?”. Maybe that is a decision that even the acres of computers at NSA cannot answer for themselves. It requires someone has to crank it in as input. It’s interesting to realize that in this super-duper universe there are still some choices that must be made by men, though we are working on eliminating that.