Sunday, May 20, 2012

The Beginning of Infinity, David Deutsch

David Deutsch's The Beginning of infinity was a fun and surprising read. Deutsch is well known as a theoretical physicist (having pioneered the idea of quantum computing), and has written very readable papers and books and given good talks at TED and elsewhere. In this book, he talks about a wide variety of systems that allow unlimited expression, growth, and progress. His goal is to show how DNA is a universal language for describing how to build varieties of living things in the same way that a Turing machine can express different kinds of computation. He talks about how the discovery of the scientific method put us on a path to learning an ever-growing set of facts about how the world works.

He comes across as very libertarian, (which Wikipedia presents matter-of-factly), though he's not strident about it at all.

His explanation of explanation is that good explanations capture details about something of interest in a way that is hard to vary; if you change any of the parts of a good explanation, you get a story that doesn't stick together, or that makes predictions that don't hold up. Bad explanations can be just-so stories, or "because the gods wanted it that way". Why did the gods want it that way? What if they change their mind or disagree? And a really good explanation adds details about facets of reality other than its primary aim.

When talking about the foundations for reasoning about morality, Deutsch demolishes the old maxim that "you can't derive an ought from an is" as a basis for rejecting facts as evidence in discussions of morality. He points out that while it's literally true, it's also the case that you don't derive physical laws from single facts. Instead facts fuel intuitions that lead to proposals for theories, and can count as evidence against particular proposed theories. If a theory runs counter to an observed fact, the theory loses. Similarly, "observed facts can be useful in criticizing moral explanations." In order to persuade people of a moral theory, proponents have to offer explanations, and when those explanations are refuted by observation, the listeners will often be skeptical.

I found this passage, on the evolutionary origins of DNA as a universal language to be incisive enough that I posted it to Google+:

Initially, the genetic code and the mechanism that interpreted it were both evolving along with everything else in the organisms. But there came a moment when the code stopped evolving yet the organisms continued to do so. At that moment the system was coding for nothing more complex than primitive, single celled creatures. Yet virtually all subsequent organisms on Earth, to this day, have not only been based on DNA replicators but have used exactly the same alpahabet of bases, grouped into three-base 'words', with only small variations in the meanings of those 'words'.

That means that, considered as a language for specifying organisms, the genetic code has displayed phenomenal reach. It evolved only to specify organisms with no nervous systems, no ability to move or exert forces, no internal organs and no sense organs, whose lifestyle consisted of little more than synthesizing their own structural constituents and then dividing in two. An yet the same language today specifies the hardware and software for countless multicellular behaviours that had no close analogue in those organisms, such as running and flying and breathing and mating and recognizing predators and prey. It also specifies engineering structures such as wings and teeth, and nanotechnology such as immune systems, and even a brain that is capable of explaining quasars, designing other organisms from scratch, and wondering why it exists.

In discussing the nature of representative democracy, Deutsch reveals his libertarianism. He starts with a very clear explanation of Arrow's impossibility theorem, (which shows that there are no possible voting systems that satisfy four simple, obvious criteriaf). Deutsch shows how that applies not only to individuals voting, but also to parliaments and legislatures, how it shows that simple math makes it irrational for voting to solve our problems. He sides with Popper in saying htat we'd be better off looking for possible consistent systems that do a good job of getting rid of bad policies and bad governments without requiring violence. He doesn't hope to find a system that wouldn't occasionally make mistakes; instead he wants a system that is willing to identify errors after the fact and backtrack.

The essence of democratic decision-making is not the choice made by the system at elections, but the ideas created between elections.

What we should be looking for is ways of organizing society that keep options open, allow invention and discovery, and are willing to backtrack. What we have now is a system that institutionalizes stasis, and makes it hard to revisit choices once made. We'd be better off with a system that allowed exploration of many alternatives to compare them, and only made binding choices once it became clear that one approach produces better outcomes in a variety of situations over the long term.

Deutsch also comes out strongly against compromise. He doesn't like proportional representation and parliamentary systems, since they enforce compromise. This has the consequence that no one's ideas are tried out in the way they intended, so everyone can continue to maintain that things would have worked out better if they hadn't had to compromise. In the long term, world was able to learn something from the failed socialist experiments in the Soviet Union, China, and several smaller countries. While some people continue to promote those ideas, most others can see that when they are tried on a large scale, they lead to bad outcomes.

Overall, I found it an engrossing, enjoyable read. Deutsch had some great explanations for some important phenomena, and pulled together commonalities between some widely disparate ideas.