A few years later, a graduate student in the then new subject of environmental science explained to me that colour television was a sign of the imminent collapse of our ‘consumer society’. Why? Because, first of all, he said, it served no useful purpose. All the useful functions of television could be performed just as well in monochrome. Adding colour, at several times the cost, was merely ‘conspicuous consumption’. That term had been coined by the economist Thorstein Veblen in 1902, a couple of decades before even monochrome television was invented; it meant wanting new possessions in order to show off to the neighbours. That we had now reached the physical limit of conspicuous consumption could be proved, said my colleague, by analysing the resource constraints scientifically. The cathode-ray tubes in colour televisions depended on the element europium to make the red phosphors on the screen. Europium is one of the rarest elements on Earth. The planet’s total known reserves were only enough to build a few hundred million more colour televisions. After that, it would be back to monochrome. But worse – think what this would mean. From then on there would be two kinds of people: those with colour televisions and those without. And the same would be true of everything else that was being consumed. It would be a world with permanent class distinction, in which the elites would hoard the last of the resources and live lives of gaudy display, while, to sustain that illusory state through its final years, everyone else would be labouring on in drab resentment. And so it went on, nightmare built upon nightmare. I asked him how he knew that no new source of europium would be discovered. He asked how I knew that it would. And, even if it were, what would we do then? I asked how he knew that colour cathode-ray tubes could not be built without europium. He assured me that they could not: it was a miracle that there existed even one element with the necessary properties. After all, why should nature supply elements with properties to suit our convenience? ... He was right in one respect: no alternative red phosphor has been discovered to this day. Yet, as I write this chapter, I see before me a superbly coloured computer display that contains not one atom of europium. Its pixels are liquid crystals consisting entirely of common elements, and it does not require a cathode-ray tube. Nor would it matter if it did, for by now enough europium has been mined to supply every human being on earth with a dozen europium-type screens, and the known reserves of the element comprise several times that amount. Beginning of infinity, David Deutsch
The recurring pattern is that experts are often good at explaining the present but less reliable at predicting the future.
Expertise is usually built around the current state of a field: its known constraints, dominant architectures, accepted tradeoffs, and recent failure modes. This makes experts valuable for operating within an established system, but it can make them less accurate when the system itself is about to change.
The color television example is a useful case. The objections were not irrational. They were grounded in the technology and economics that observers could see at the time: limited picture quality improvements, dependence on scarce materials, high cost, and the possibility that the product would remain a luxury for elites. Those claims were coherent if one assumed that the relevant production methods, materials, and demand patterns would remain roughly fixed. Technological progress often works by changing the constraint set rather than by optimizing inside it.
History provides many examples. Heavier-than-air flight, the four-minute mile, reusable rockets, and practical electric cars were each treated at various times as unrealistic or impossible. In every case, the eventual solution did not require violating physics. It required different designs, better engineering, lower costs, or supporting technologies that were not yet mature.
When an expert says something cannot be done, the first question should be: is this a law of physics or a statement about current conditions?
The second question should be: which assumptions make the impossibility claim true? If those assumptions changed, would the conclusion still hold?
Progress is often hard to forecast from inside the existing system because progress changes the system itself. Expertise remains essential for building, operating, and improving what already exists.
... But all triumphs are temporary. So to use this fact to reinterpret progress as ‘so-called progress’ is bad philosophy. The fact that reliance on specific antibiotics is unsustainable is only an indictment from the point of view of someone who expects a sustainable lifestyle. But in reality there is no such thing. Only progress is sustainable. ... Trying to predict what our net effect on the environment will be for the next century and then subordinating all policy decisions to optimizing that prediction cannot work. We cannot know how much to reduce emissions by, nor how much effect that will have, because we cannot know the future discoveries that will make some of our present actions seem wise, some counter-productive and some irrelevant, nor how much our efforts are going to be assisted or impeded by sheer luck. Tactics to delay the onset of foreseeable problems may help. But they cannot replace, and must be subordinate to, increasing our ability to intervene after events turn out as we did not foresee. If that does not happen in regard to carbon-dioxide-induced warming, it will happen with something else. ... Strategies to prevent foreseeable disasters are bound to fail eventually, and cannot even address the unforeseeable. To prepare for those, we need rapid progress in science and technology and as much wealth as possible. Beginning of infinity, David Deutsch