Sunday, November 1, 2009

Diax's Rake

In Neal Stephenson's wonderful novel Anathem, a character called Diax drives the numerologers out of the Temple of Orithena using a garden rake.

This legendary rake gives its name to a philosophical principle, Diax's Rake:

Be careful of believing things because you want to believe them.

In the book, it is also used as a verb. One can rake a sentence of its emotional content. At one point, a character speaks of "reforms". His interlocutor rakes his sentence, pointing out that the word "reforms" carries with it a judgement that the reforms were necessary. When they agree to use "changes" instead, the character of their argument becomes different.

Since I read this, situations where the maxim is useful have occurred to me almost every day.

For instance, the theory of evolution by natural selection is a peculiarly horrible idea. It implies that life is a terrible, and extraordinarily wasteful, war of all against all, and that almost every feature of every form of life is the result of the deaths of millions of innocent creatures whose only fault was not to have the feature.

Many people choose not to believe this awful idea because they have a theory that they would prefer to believe.

The most obvious current example is religious creationists, who have the much more comforting idea of a God of love, who cares about the fall of every sparrow.

There's an equally persistent view that evolution is a continuous process of improvement towards perfection. In this view, humanity is the most evolved of all the living creatures.  This is one of the most dangerous evolutionary fallacies. In fact the common cold virus has done just as much evolving as we have, and is in many senses much more perfectly adapted to its environment than we are.

Some people who call themselves Darwinists positively glory in the horror and cruelty of the Darwinian view of the world. Sometimes they come to believe that the theory of evolution has some sort of moral content, and that what is natural is also morally right.

The scientific establishment of the Soviet Union, mostly educated, clever men, could also not bring themselves to believe in the Darwinian theory, preferring various forms of Lamarckism. Lamarckism is also an evolutionary theory, but based on the transmission of acquired characteristics, such as the sons of blacksmiths inheriting their father's strength. The problem is that there's very little evidence that anything like this happens.

Since the emotional value of a theory has nothing to do with its truth, it strikes me that to prefer one theory over another because of its moral content is a fundamental error.

But it seems to be one which is very difficult to avoid.

I think that Diax's Rake is a philosophical fundamental, as useful as Occam's Razor (which also makes an appearance in Anathem, under the name of Gardan's Steelyard).

If a concept is that useful, it is very important to give it a name.

But I can't think of any philosophical principle that Diax's Rake is a paraphrase of.

Perhaps we should adopt it, and just call it by the name Stephenson gave it.


  1. "Be careful of believing things because you want to believe them."

    I think we call that the confirmation bias (

  2. This was first articulated by Francis Bacon. He was an amazing thinker almost 500 years and today. I think this is who Stephenson was alluding too. Anathem is a great book.

  3. The Anathem wiki points to Thucydides, who said:

    "[I]t is a habit of mankind to entrust to careless hope what they long for, and to use sovereign reason to thrust aside what they do not desire."'s_Rake

  4. The closest thing to Diax's Rake I've seen anywhere is is what's called the Litany of Tarski:
    "If the sky is blue, I wish to believe the sky is blue. If the sky is not blue, I wish to believe that the sky is not blue."