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General disclaimer about the handwaving nature of these articles While this blog features mostly longform content, the issues discussed and thinkers presented deserve their own 3-parts university course (and usually they have one).<br>Everything you read here is a handwaving summary, lacking to the point of liability.<br>Hopefully it will still be an interesting read.

Kuhn! At the Software Industry - Part 1 - Setting the scene

In this two-part series we’ll trace the dynamics of a generic software project’s descent into crisis testing, through the lens of Kuhn’s normal-science versus crisis-science distinctions and what they suggest about methodology as such.

The first part will walk through an overview of Kuhn’s work, and suggest a mapping of his vocabulary onto a modern software environment. The second part will add some much needed nuance through two post-Kuhnian voices making their cases for and against method.

Setting the stage - your dashboard is a Wicked-themed bright green, while the customers are opening ticket after ticket full of impossible behaviours. We’re looking for an account of how a competent team gets here that doesn’t trivially reduce to “somebody should have written more test cases”.

Let’s boogie.

Prologue: Popper sets the stage

A repeating claim in the blog (well, I expect it to repeat) is that if someone knows any philosophy of science at all, they probably know about Popper and his concept of refutation. That’s doubly so in the testing world, as a handwaving summary of Popper usually maps quite well to a vague notion of what testing boils down to.

Let’s start with a quick rundown of Hume’s riddle of induction, which is the problem Popper was reacting to. Simply put, Hume famously claimed no finite number of observations can support a universal claim, or any kind of projection from the observed instances to the next unobserved instance.

So take the textbook version of this from Hempel: even if every piece of copper that was ever observed conducted electricity, this supposedly gives no rational justification to conclude that the next piece of copper will also conduct electricity, let alone generalise to the rule that all copper conducts electricity. Note - Hume claimed there’s NO justification. Zero.

Induction, according to Hume, has no rational justification. Yet science, which appears to be built out of and on top of induction, has an excellent track record. Not to mention that if induction is broken, even getting out of bed becomes straight up risky - how can you know you won’t just float up to space? Without induction, all bets are off1<br>Hume’s own conclusion was actually different. He didn’t say we should stop using induction, just that we don’t have a strictly rational justification for doing so. Basically Hume’s point is that we’re not completely rational, and that’s a good thing.

Throughout the centuries there’ve been countless attempts to answer Hume, and we’ll undoubtedly cover a lot of them in the blog. Popper’s answer is somewhat radical and can be summarised as “Hume is right, but it doesn’t matter”. According to Popper, science doesn’t (or rather, shouldn’t) run on induction at all.

Popper’s view is that science, in as much as we see its aim as the pursuit of true universal theories, can’t pursue this goal inductively (since no logically valid principle of induction has ever been devised, i.e. Hume’s riddle). He therefore proposes a method for our acceptance and practical demarcation efforts - a method that relies solely on deduction. Remember that logically, no amount of finite evidence can confirm a universal claim through deduction; but a single piece of counter evidence can refute a universal claim deductively (Quine will have something to say about that, but let’s keep it simple).

So the foundations of the scientific method he proposed (“science”, being a somewhat open-ended term that only gets us so far) are conjecture and refutation. In VERY handwaving broad strokes, it would go something like this: Propose something bold, derive what it logically forbids, go looking for the forbidden thing. Found it? Great. As the theory and the observation can’t both be right, if we accept the forbidden thing, we have to reject the theory as having been falsified. Didn’t find it? Well, we take the theory not to have been falsified for now . Not proven, mind you, just not yet falsified. Popper set this up as a normative standard for science, alongside other considerations the will be discussed more seriously in another article. For now, a sufficient first approximation of Popper’s view for our needs is that an empirical theoretical system should be deemed scientific if it can be refuted. Meaning that it forbids a state of affairs we have the means to show actually is the case. If nothing could falsify it, Popper excludes it as an empirical statement of science.

(The above is a far...