The Logical Fallacy

Nary a week goes by without seeing a post by a programmer, for programmers, on the subject of logical fallacies in arguments. This week’s, courtesy of hacker news, is not egregious, enlightening, or indeed different in any way from the usual torrent. It is merely the one that prompted me into writing this article. The most frequent, and most severe, logical fallacy I encounter among programmers is this one:

  • basing your argument on logic.

Now, obviously, for a fallacy to be recognised it needs to have a Latin name, so I’m going to call this one argumentum ex logica.

Argumentum ex logica is the fallacious reasoning that the best course of action for a group of people is the one that can be arrived at by logical deduction. No need to consider the emotions of the people involved, or the aesthetic properties of any potential solutions. Just treat your workplace like your high school debating club, pick (seemingly arbitrarily) some axioms, and batter your way through to your preferred conclusion.

If people disagree with you on (unreasonable) emotional grounds, just name their logical fallacies so you can overrule their arguments, like you’re in an episode of Ally McBeal and want their comments stricken from the record. If people manage to find a flaw in the logic of your argument, just pick a new axiom you’d never mentioned before and carry on.

The application of the argumentum ex logica fallacy is frequently accompanied by descriptions of the actions of “the brain”, that strange impish character that sits inside each of us and causes us to divert from the true path of Syrran of Vulcan. Post hoc ergo propter hoc, we are told, is an easy mistake to make because “the brain” sees successive events as related.

Here’s the weird thing. We all have a “the brain” inside us, as an important part of our being. By writing off “the brain” as a mistaken and impure lump of wet fat, programmers are saying that they are building their software not for humans. There must be some other kind of machine that functions on purely logical grounds, for whom their software is intended. It should not be.

Applications and Spelling of Boole

While Alan Turing is regarded by many as the grandfather of Artificial Intelligence, George Boole should be entitled to some claim to that epithet too. His Investigation of the Laws of Thought is nothing other than a systematisation of “those universal laws of thought which are the basis of all reasoning”. The regularisation of logic and probability into an algebraic form renders them amenable to the sort of computing that Turing was later to show could be just as well performed mechanically or electronically as with pencil and paper.

But when did people start talking about the logic of binary operations in computers as being due to Boole? Turing appears never to have mentioned his name: although he certainly did talk about the benefits of implementing a computer’s memory as a collection of 0s and 1s, and describe operations thereon, he did not call them Boolean or reference Boole.

In the ACM digital library, Symbolic synthesis of digital computers from 1952 is the earliest use of the word “Boolean”. Irving S. Reed describes a computer as “a Boolean machine” and “an automatic operational filing system” in its abstract. He cites his own technical report from 1951:

Equations (1.33) and (1.35) show that the simple Boolean system, given in (1.34) may be analysed physically by a machine consisting of N clocked flip flops for the dependent variables and suitable physical devices for producing the sum and product of the various variables. Such a machine will be called the simple Boolean machine.

The best examples of simple Boolean machines known to this author are the Maddidas and (or) universal computers being built or considered by Computer Research Corporation, Northrop Aircraft Inc, Hughes Aircraft, Cal. Tech., and others. It is this author’s belief that all the electronic and digital relay computers in existence today may be interpreted as simple Boolean machines if the various elements of these machines are regarded in an appropriate manner, but this has yet to be proved.

So at least in the USA, the correlation between digital computing and Boolean logic was being explored almost as soon as the computer was invented. Though not universally: the book “The Origins of Digital Computers” edited by Brian Randell, with articles from Charles Babbage, Grace Hopper, John Mauchly, and others, doesn’t mention Boole at all. Neither does Von Neumann’s famous “first draft” report on the EDVAC.

So, second question. Why do programmers spell Boole bool? Who first decided that five characters was too many, and that four was just right?

Some early programming languages, like Lisp, don’t have a logical data type at all. Lisp uses the empty list to mean “false” and anything else to mean true. Snobol is weird (he said, surprising nobody). It also doesn’t have a logical type, conditional execution being predicated on whether an operation signals failure. So the “less than” function can return the empty string if a<b, or it can fail.

Fortran has a LOGICAL type, logically. COBOL, being designed to be illogical wherever Fortran is logical, has a level 88 data type. Simula, Algol and Pascal use the word ‘boolean’, modulo capitalisation.

ML definitely has a bool type, but did it always? I can’t see whether it was introduced in Standard ML (1980s-1990), or earlier (1973+). Nonetheless, it does appear that ML is the source of misspelled Booles.

Digital Declutter

I’ve been reading and listening to various books about the attention/surveillance economy, the rise of fascism in the Anglosphere and beyond, and have decided to disconnect from the daily outrage and the impotent swiping of “social” “content”. The most immediately actionable advice came from Cal Newport’s Digital Minimalism. I will therefore be undertaking a digital declutter in May.

Specifically this means:

  • no social media. In fact I haven’t been on most of them all of April, so this is already in play. By continuing it into May, I intend to do a better job of choosing things to do when I’m not hitting refresh.
  • alerts on chat apps on for close friends and family only.
  • streaming TV only when watching with other people.
  • Email once per day.
  • no RSS.
  • audiobooks only while driving.
  • Slack once per day.
  • Web browsing only when it progresses a specific work, or non-computering, task.
  • at least one walk per day, of at least half an hour, with no technology.
  • Phone permanently in Do Not Disturb mode.

It’s possible that I end up blogging more, if that’s what I start thinking of when I’m not browsing the twitters. Or less. We’ll find out over the coming weeks.

My posts for De Programmatica Ipsum are written and scheduled, so service there is not interrupted. And I’m not becoming a hermit, just digitally decluttering. Arrange Office Hours, come to Brum AI, or find me somewhere else, if you want to chat!

What’s on the other channel?

I run a company, a mission-driven software consultancy that aims to make it easier and faster to make high-quality software that preserves privacy and freedom. On the homepage you’ll find Research Watch, where I talk about research papers I read. For example, the most recent article is Runtime verification in Erlang by using contracts, which was presented at a conference last year. Articles from the last few decades are discussed: most is from the last couple of years, nothing yet is older than I am.

At de Programmatica Ipsum, I write on “individuals, interactions, and the true valuation of the things on the left” with Adrian Kosmaczewski and a glorious feast of guest writers. The most recent issue was on work, the upcoming issue is on programming history. You can subscribe or buy our back-catalogue to read all the issues.

Anyway, those are other places where you might want to read my writing. If people are interested I could publish their feeds here, but you may as well just check each out yourself :).

Half a bee

When you’re writing Python tutorials, you have to use Monty Python references. It’s the law. On the 40th anniversary of the release of Monty Python’s Life of Brian, I wanted to share this example that I made for collections.defaultdict that doesn’t fit in the tutorial I’m writing. It comes as homage to the single Eric the Half a Bee.

from collections import defaultdict

class HalfABee:
    def __init__(self):
        self.is_a_bee = False
    def value(self):
        self.is_a_bee = not self.is_a_bee
        return "Is a bee" if self.is_a_bee else "Not a bee"

>>> eric = defaultdict(HalfABee().value, {})
>>> print(eric['La di dee'])
Is a bee
>>> print(eric['La di dee'])
Not a bee

Dictionaries that can return different values for the same key are a fine example of Job Security-Driven Development.

Pythonicity

The same community that says:

There should be one– and preferably only one –obvious way to do it.

Also says:

So essentially when someone says something is unpythonic, they are saying that the code could be re-written in a way that is a better fit for pythons coding style.