(2024-06-02) Maciver The Manual That Solves All Your Problems

David R. MacIver: The Manual that solves all your problems. Paul Erdos had a concept of The Book, in which God had written down the shortest most elegant proof of every conceivable mathematical problem

I haven’t really been a mathematician in some 20 years. I’m still interested in mathematics, but not to the same degree, and I no longer quest after the Book. Instead, I’m looking for the Manual.

The Manual is where you go when you have a problem, or want your life to be better in some way.

Engineers reliably use a mix of their own working knowledge and the manual, with a general distrust of the manual as a source of truth because of how necessarily they oversimplify the world and try to replace skilled understanding with mechanical rote.

You don’t need the manual when you already deeply understand the problem, you need it when you start to feel out of your depth.

a sufficiently comprehensive manual like this for anything has to be a sufficiently comprehensive manual for everything, because everything is connected to everything else.

Importantly, the Manual is not a genie. It doesn’t know anything about your situation, it doesn’t do anything for you, it doesn’t even promise success if you follow its procedure. It merely provides clear procedures for you to follow that are more likely to work than anything else you might try.

This, necessarily, includes diagnosis

“That seems like a problem. Have you tried solving it?” is one of my catch phrases, and I think one helpful way to start on something like this is “If I looked in the Manual, what would it tell me to do?”

When is the Manual useful?

it should rarely need to be consulted

The purpose of having the shop manual is that, even when you don’t use it, it gives you a reliable slow fallback plan that means that many more problems are solvable than your current expertise allows for.

When you lack relevant expertise it can take you through the longer, slower, methods, some of which will result in you developing expertise, some of which will help you work around your lack.

I think a good way of thinking about this is that the manual gives you a way of operating competently inside your zone of proximal development

On the impossibility of the Manual

Even within a given time and place and physical context, the Manual has to find out all sorts of things about you before it makes sense to start problem solving.

In some sense it makes more sense to think of the Manual as ever-changing and personalised

I don’t like this view. The reason I don’t like this view is that it makes it very hard to think about shared access to the Manual

to the degree we are similar people we will get similar answers

Despite the impossibility of reading from the Book, Erdős frequently declared that a proof was or wasn’t from it. Erdős could get away with this because he had almost unparalleled mathematical taste

I imagine the Manual as consisting of essentially two types of material:

A collection of very well explained procedures

An organising diagnostic tool that tells you which procedures to perform

The hard part of accessing the Manual is the diagnostic tool.

a very general purpose procedure that works in a lot of different scenarios is “Turn it off and on again” - (heuristic)

The result is that it’s likely to be a very commonly referenced procedure in the manual, and I think we can often glimpse what these look like.

Their two key characteristics are:
They are relatively simple.
They can be usefully applied in a reasonable variety of situations.
Applying them is unlikely to be a bad idea, or the procedure comes with built ins to make sure you check that it’s safe first.

How do you figure out these procedures? Well, trial, error, and refinement (iterative)

The hard part is the decision tree

The thing about super formalised decision procedures is that they’re mostly not how experts make decisions. They’re useful when you don’t know what you’re doing

expert decision making isn’t this sort of formalized decision tree of if A then do B else do C, it’s pattern matching based.

You see a situation, it reminds you of something. (Cognitive Flexibility Theory)

This is a much more intuition based process than the Manual’s detailed procedures, which is unfortunate if you’re in a novel situation where you don’t have much intuition

you try to become an expert in the procedures rather than the problems

This means that when you encounter a novel problem you can try to go “OK, what procedure do I apply to this?”

This may or may not work, but you win either way: Either you achieve something, or you learn something more about the procedure and where it’s useful.

When this happens it’s often worth taking a little time to pause and reflect about it to really increase the learning - do a mini retrospective

often like a minute or two of reflection is enough

The big advantage in terms of thinking this way is that these procedures are refinable, and learnable, and they turn your problem solving strategies into concrete operations that you can work on and improve.

write it down, because you’ve glimpsed a fragment of the divine, and that should be remembered and shared so that future you and others can benefit from it.

Here are some books that feel vaguely related to me that I think you’ll enjoy:

Talking about machines by Julian Orr - this is a great book about photocopier repair technicians working at Xerox. (Tacit Knowledge)

Working knowledge by Douglas Harper

Sources of Power by Gary Klein -


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