Gradual Progress

A refutation of David Deutsch’s culture of knowledge growth

Conjecture Magazine


Photo by Massimo Virgilio on Unsplash

I. The idea of progress

If you’re interested in the idea of progress, it’s hard to escape the gravitational pull of David Deutsch’s beautifully argued vision of progress. In The Beginning Of Infinity and The Fabric Of Reality, he lays out a clear vision for what drives us to explore and grow as a species.

According to Deutsch, for most of human history, knowledge was stagnant. Sure, there were the occasional oases, like Pericles’ Athens, but they were unique, fragile, and fleeting. This all changed with the Enlightenment. Galileo discovered the rings around Saturn and invented telescopes, and Newton discovered the simple mathematics that prescribed the path of the heavens.

I see human history as a long period of complete failure — failure, that is, to make any progress. Now, our species has existed for maybe 50,000, 100,000, or 200,000 years. The vast majority of that time, people were alive, they were thinking, they were suffering, they wanted things. But nothing ever improved. The improvements that did happen happened so slowly that geologists can’t distinguish the difference between artifacts from one era to another with a resolution of 10,000 years. So, from the point of view of a human lifetime, nothing ever improved, with generation upon generation upon generation of suffering and stasis.

The thesis, in a nutshell, is that we as a species had a step change in our ability to grapple with the universe around us in the 17th century, during the Enlightenment and the Scientific Revolution. Discover a question, propose an explanation, criticize that explanation, and revise with improved explanations ad infinitum; we learned to learn. We created a process of becoming less wrong, tolerating dissenting views, sweeping away previously existing arguments from authority and rules of thumb, all to create a culture that focuses on discovering the truth and producing progress.

But a key question is whether this was indeed a step change, as Deutsch suggests, or if it was a gradual outgrowing of the multiple strands of scientific growth that had happened in the past. Is the Enlightenment as Deutsch describes, a transformative period, or is it a natural tunnel that any sufficiently progress-minded society would have passed through?

Part of the argument for the step change view is that the Enlightenment and the Scientific Revolution changed the way we thought of the world. We created a culture that prized innovation. Dr. Anton likes to discuss the epidemic of innovation: once a spark is lit somewhere, there’s likely to be a wildfire spreading through the society.

The argument is that this new way of thinking, the scientific way of hunting for better explanations about the world, with hypotheses and experiments to corroborate them, is the crux of all our progress. And once it was invented, it spread like wildfire to all parts.

The problem is that this belies the entire endeavour we’ve been on since the beginning of civilisation. The (European) Enlightenment can be said to be the outcome of several small-ish domains that underwent gradual changes in the 17th and 18th centuries, finally melding with each other for an explosion of potential.

II. Path dependence in technological breakthroughs

If we were to look at the technological and scientific growth we have seen across domains, and map them out to see what breakthroughs they depended on, we’d see a table that looks something like this.

Across a variety of categories, across the three industrial revolutions (called IR above), we see substantial dependencies that exist amongst individual breakthroughs. Even the ones that seem miraculous successes borne out of our inclination for knowledge came from prior knowhow, which itself relied on prior knowhow, and so on.

Even when you go back to the pre-scientific era, ancient medicine relied on some analyses of visible symptoms, a good random mix of herbs that worked, and plenty of trial and error. It all resulted in something that, all things considered, worked surprisingly well. This is because there was a clear path to getting better explanations through trial and error and a minimum of theory which, even if not correct in substance, had a broadly useful framework.

Similarly, there were certain fields, such as in architecture, military, or astronomy, where the explanations seemed to come much before the Enlightenment period. And not in a foundationalist way, which Deutsch decries, but rather in a predictive fashion, such that they kept improving over time.

Deutsch himself comments on the fact that we didn’t need to reinvent bridges when we learnt that Newton’s laws were correct, or later when we learnt they were incomplete. This is because bridge building had a progress independent of its scientific foundations. So why would we prioritise the foundational explanations over the practical?

The technological advances of the 15th, 16th, and 17th centuries helped philosophers change their attitude towards the crafts. As William Shea says:

“The positive valuation of the crafts and the growing admiration for technological innovation that we find in the fifteenth century was reinforced in the sixteenth by a number of authors on mining, metallurgy and machines. … New tools offered new means of investigation.”

This is not to say there were no “breakthroughs”.

The pioneers of the Scientific Revolution owe much to those who came before them, but it would be wrong to claim that modern chemistry is simply an offshoot of alchemy or Galilean mechanics merely the outcome of medieval scholasticism. The ‘newness’ so loudly heralded in books and essays written at the time of the Scientific Revolution was not merely a sale’s pitch or media hype. It mirrored a genuine change in the realm of knowledge, even when the change was less profound and less satisfactory than their authors believed.

The creation of the telescope, brought about by extraordinary craftsmanship, shrank the heavens to fit in our palms. It dealt evidence against Ptolemy but also showed the evidence of other celestial bodies and countless stars, which was a pretty brutal epistemological blow.

But thinking of this blow as a triumph of the particular method is missing the forest for the trees. It’s the gradual accumulation of multiple lines of knowledge that resulted in our ability to make the very thing that made the observation possible. Whether it’s staring at the heavens with the telescope or staring at the miniscule through the microscope, these tools literally expanded our world, and therefore our thought.

The expansion of thought facilitated through these advances meant that we could have a revolution in the first place. The primacy shouldn’t be on the fact that we happened to have this remarkable achievement, but rather on the fact that to get to such an achievement required the efforts and advances in a large number of fields. Only in their coming together was escape velocity reached.

III. Standing on the shoulders of giants

So when Saint Aquinas writes about the importance of investigation into natural phenomena like lightning, which the Franciscans take to mean investigations into physics, and which Galileo builds on with the telescope, that progression of events seems remarkably path-dependent!

It is intriguing that the beginnings of our scientific method came constrained within the “mixed mathematical” sciences of optics and astronomy. Sciences where observation reigned supreme were in high demand.

While the science of motion and astronomy went to great heights, this did not cause a behavioural change. If that was the case, we should’ve seen their methods applied to all other aspects of science in short order. But that’s not what we saw. Instead, we saw a gradual process of tool and craft co-evolution such that new theories could be tested, and pertinent experiments could be developed. We might even characterise part of that process as a movement from a mathematical and theoretical science to a practical science!

When Deutsch ascribes to the Enlightenment a “jump to universality” such that it moved us from “just doing things” to now creating and evaluating hypotheses to master nature, that too is basically brushing aside all of history as a sort of “termites nest” style accident.

But the Scientific Revolution is less a de novo phenomenon that unlocked an achievement hitherto unknown to man, but rather another step in the gradual exploration of nature that we were taking anyway.

If we cast our eyes back into history, we can see epistemology developing from the time of Epicurus, geometry flowing from axioms from Euclid, systematic observations from Ptolemy and Ibn Haytham, and treatises on how to conduct observations to form hypotheses and then experiments to test them from Bacon in the 1200s. We truly stand on the shoulders of giants.

One of the consequences of living on an exponential curve is that for the longest time it looks like a straight line. But to mistake it for one and ascribe some sort of peculiar magic to the inflection point is folly, too.

Infinities make for confusing analogies. I prefer to think of our knowledge creation as an expanding wave. As the frontier expands, so does the area we now need to explore. As the frontier expands with each gained piece of knowledge, so does the number of possible paths we have to take.

Reading Deutsch is akin to reading a great poem, something of Yeats or Coleridge or Dylan Thomas. It energises your mind and enervates the senses with which to approach the very question of progress. And yet some parts of it seem allegorical. This isn’t a negative. If you need to convince others of the rightness of a belief system, it’s perhaps the only way.

Gradualism doesn’t diminish the role for inspiration or our desire to do better. If anything, it’s helpful to show us how we come to create all that we see around us.

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Rohit is a Director at Unbound, a venture capital firm based in London. Previously he was with McKinsey, helping startups and the Fortune 500 on technology and innovation. He writes a newsletter about progress, applied economics and innovation at and can be found on Twitter at @krishnanrohit.