This also sounds a lot like Elmer Gates' approach to learning new things and coming up with inventions.

Gates’s “mind-using” strategies look very different from modern and traditional learning practices. Gates’s theory of “brain-building” fused radically empiricist and inductivist philosophy with a belief in the mind’s adaptability, and his “art” reflects that. Early on in his studies, Gates observed that acquiring the right higher level concepts depended heavily on having the right foundational experiences. Hence, to learn a new scientific field, Gates would start by gathering the “sensory experiences” that constituted the raw data of that science. In the case of mechanics, this might involve replicating key experiments related to things like gravity or fiction. In the case of chemistry, Gates supposedly replicated the experiments described in multiple textbooks himself. In the case of weaving, which Gates was once challenged to apply his method to (which he did successfully, inventing multiple new devices), we have the following quote regarding how Gates’s went about the initial steps:

I secured letters of introduction to practical weavers and loom makers, and with the aid of several assistants made a systematic search of the technical literature. By actual observation of looms and methods of weaving I built over my brain with reference to that subject; acquiring an the images, concepts, ideas, and thoughts that six weeks’ continuous effort made possible.

Once Gates had had the necessary sensory experiences, he’d move on to the next step of “refunctioning” them. Refunctioning (coined by Gates) refers to mentally reviewing the experiences and observations acquired from the science until they “became more vivid, much more clearly minted and complete, while the processes of states acquired much greater celerity and efficiency.” As far as I can tell, Gates would then move on to repeating the process but for images, concepts, and thoughts (higher levels of abstraction) that emerged from repeatedly reviewing the raw experiences and studying their relationships. The following passage contains the best description I could find of this part of the process:

Then he related each concept to the others, which gave many new and true ideas (to be temporarily recorded until experimentally verified). Every new concept always implied a number of new ideas; and for the first time, to relate new concepts was always a rich opportunity for new ideas.

Another example from the lab. My labmate is running a microfluidic system to make nanoparticles. She's trying to make them monodispersed (all the same size). What she'll publish is very precise measurements of the size distribution of the nanoparticles, which she'll obtain from the MasterSizer.

However, it's a 30 minute round trip walk to use it. And every MasterSizer reading is just a point in time. What she'll use to make the decision about whether or not to measure the nanoparticles is purely qualitative. She's got a microscope hooked up to a computer screen that's displaying the nanoparticles flowing through as they're created. She can see clearly that they're monodispersed, and can tell by sight what the effect is of changing the speed of the oil and aqueous phases, the angle of the syringes, or the ratio of the flow rates. Not to mention the effect of bumps, dust particles, and so on. It's a continuous, dynamic, high-data way to observe - a firehose of information.

The figure that will ultimately be published will capture only a small piece of that, and it will be a far less informative piece of information than simply standing there and watching the nanoparticles stream by - or an informal conversation with her. But that MasterSizer measurement is what may convince other researchers that she's had success, or that her techniques are worth trying. They'll have to set up their own firehose to really learn about those monodispersed nanoparticles. The paper is, in a way, just advertising, and maybe a third of the way to an instruction manual.

Well stated, good post!

You might enjoy my paper on this topic, where I present other approaches to measurement, especially in the presence of adversarial pressure, which you didn't really discuss. I also think that the idea of metric design, which I explored, gets into more detail about how I think you can practically do measurement better.

(The Feynman story remains unconfirmed.)

Great post!

This also reminds me of Tal Yarkoni's paper on what he calls the generalizability crisis in psychology. That's the fact that psychological experiments measure a very specific thing that's treated as corresponding to a more general thing. Psychologists think that the specific thing measures the more general thing, and Yarkoni argues that they're not measuring what they think they're measuring.

One of his examples is about the study of verbal overshadowing. This is a claimed phenomenon where if you have to verbally describe what a face looks like, you will be worse off at actually recognizing that face later on. The hypothesis is that producing the verbal description causes you to remember the verbal description, while remembering the actual face less well - but the verbal description inevitably contains less detail. This has been generalized to the broader claim of "producing verbal descriptions of experiences impair our later recollection of them".

Yarkoni discusses an effort to replicate one of the original experiments:

Alogna and colleagues (2014) conducted a large-scale “registered replication report” (RRR; Simons, Holcombe, & Spellman, 2014) involving 31 sites and over 2,000 participants. The study sought to replicate an influential experiment by Schooler and Engstler-Schooler (1990) in which the original authors showed that participants who were asked to verbally describe the appearance of a perpetrator caught committing a crime on video showed poorer recognition of the perpetrator following a delay than did participants assigned to a control task (naming as many countries and capitals as they could). Schooler & Engstler-Schooler (1990) dubbed this the verbal overshadowing effect. In both the original and replication experiments, only a single video, containing a single perpetrator, was presented at encoding, and only a single set of foil items was used at test. Alogna et al. successfully replicated the original result in one of two tested conditions, and concluded that their findings revealed “a robust verbal overshadowing effect” in that condition.

Let us assume for the sake of argument that there is a genuine and robust causal relationship between the manipulation and outcome employed in the Alogna et al study. I submit that there would still be essentially no support for the authors’ assertion that they found a “robust” verbal overshadowing effect, because the experimental design and statistical model used in the study simply cannot support such a generalization. The strict conclusion we are entitled to draw, given the limitations of the experimental design inherited from Schooler and Engstler-Schooler (1990), is that there is at least one particular video containing one particular face that, when followed by one particular lineup of faces, is more difficult for participants to identify if they previously verbally described the appearance of the target face than if they were asked to name countries and capitals. [...]

On any reasonable interpretation of the construct of verbal overshadowing, the corresponding universe of intended generalization should clearly also include most of the operationalizations that would result from randomly sampling various combinations of these factors (e.g., one would expect it to still count as verbal overshadowing if Alogna et al. had used live actors to enact the crime scene, instead of showing a video). Once we accept this assumption, however, the critical question researchers should immediately ask themselves is: are there other psychological processes besides verbal overshadowing that could plausibly be influenced by random variation in any of these uninteresting factors, independently of the hypothesized psychological processes of interest? A moment or two of consideration should suffice to convince one that the answer is a resounding yes. It is not hard to think of dozens of explanations unrelated to verbal overshadowing that could explain the causal effect of a given manipulation on a given outcome in any single operationalization.

This verbal overshadowing example is by no means unusual. The same concerns apply equally to the broader psychology literature containing tens or hundreds of thousands of studies that routinely adopt similar practices. In most of psychology, it is standard operating procedure for researchers employing just one experimental task, between-subject manipulation, experimenters, testing room, research site, etc., to behave as though an extremely narrow operationalization is an acceptable proxy for a much broader universe of admissible observations. It is instructive—and somewhat fascinating from a sociological perspective—to observe that while no psychometrician worth their salt would ever recommend a default strategy of measuring complex psychological constructs using a single unvalidated item, the majority of psychology studies do precisely that with respect to multiple key design factors. The modal approach is to stop at a perfunctory demonstration of face validity—that is, to conclude that if a particular operationalization seems like it has something to do with the construct of interest, then it is an acceptable stand-in for that construct. Any measurement-level findings are then uncritically generalized to the construct level, leading researchers to conclude that they’ve learned something useful about broader phenomena like verbal overshadowing, working memory, ego depletion, etc., when in fact such sweeping generalizations typically obtain little support from the reported empirical studies.

First Law of Experiment Design: you are not measuring what you think you are measuring.

In a way, this is just a corollary to the good, old-fashioned "correlation does not imply causation" principle. I guess the important difference is that this is a warning directed at experimenters who tend to assume that they know better.

Second Law of Experiment Design: if you measure enough different stuff, you might figure out what you’re actually measuring.

Before COVID, my manager's manager would semi-regularly put on a multi-day training course where he would teach everyone in his organization about the process of "Design of Experiments" (DOE) (https://en.wikipedia.org/wiki/Design_of_experiments). I work with other data scientists, statisticians, biochemist, and engineers, often performing experiments with medical devices, so this is relevabt to all of us.

The idea behind a DOE is to create a mutifactorial experimental design that tests the effects of many factors at once. The first step is to brainstorm all possible factors that may influence the experimental results (often using a fishbone diagram [https://en.m.wikipedia.org/wiki/Ishikawa_diagram] to focus on factors arising from Materials, Method, Measurement, Machine, Man, or "Mother Nature"). Each factor is then labelled as either control (C, factors fixed throughout all parts of the experiment), noise (N, random factors that cannot/won't be controlled for but may cause some variation in the results), or experimental (X, factors to be caried systematically to test for their effects).

Next, high and low settings are chosen for each X factor, and all possible combinations of settings are arranged in a hypercube. Instead of experimenting on one factor at a time with enough repetitions to build up statistical significance, you can perform just a few repetitions at each corner of the hypercube. You can still use the results to look at single-factor contributions to the experimental effect by aggregating data from all corners of the low side and high side of the hypercube along one dimension. But you can also look at the impact of factor interactions and the nonlinearities that result, which would have acted as hidden confounders in more traditional single-factor experiments.

I liked how this method gave a systematic way of thinking about multifactorial experimental effects. Such experiments tend to uncover a lot more information about a system than you would see otherwise. To actually tease out the underlying causal mechanisms at work, though, would require deeper statistics and modeling than we ever got into in that course.

When doing quantified self-experiments, people sometimes argue for the virtues of blinding. In quantified self-experiments, blinding means measuring less. It means not exposing yourself to data about reality. "Measure Lots of Things" frequently means engaging in less blinding. 

Modern work on causality (e.g. Pearl) largely solves that problem - if we measure enough stuff.

It seems like Pearl's work is so hard to put into practice that I didn't really get good examples when I asked for them on LessWrong. 

Do you think Pearl's work is more directly useful, why do you think I didn't get more practical examples of LessWrongers who used it?

Should this be named... the Wentworth's Law of Measurement?

Basically, we have an almost religious reverence for high-powered decent-effect-size low-p-value statistical evidence, and we fail notice when these experiments acquire their bayes factors because they measure something incredibly narrow and is therefore unlikely to generalise to whatever gears-level models you're entertaining.

It has the same problem as deferring to experts. The communication suffers a bandwidth problem^[1], and we frequently delude ourselves into believing we have adopted their models as long as we copy their probabilities on a very slim sample of queries they've answered.

1. ^{^}

   I know of no good write-up of the bandwidth problem in social epistemology but Owen Cotton-Barrat talks about it here (my comment) and Dennett refers to it as the "Daddy Is a Doctor" phenomenon.

The measurement of lots of other things leads to the pathology of data mining rather than trying to find the correct causative variable.  The better experimental technique is to sequentially investigate each confounding variable and try to ensure they are eliminated.  Sometimes this can be hard, but that is no excuse not to do properly CONTROLLED experiments rather than reporting noise.

Data mining is so problematic that medical journals have insisted that the experiment hypothesis is defined in advance so that unexpected variables with significant p-values are not reported instead (p-hacking).  

I would far rather experimenters do the 1-bit experiment and then if the result doesn't falsify the hypothesis, think about other explanations for the result and check those variables in the same way.  Good experimentation is not for the lazy.