Epistemic and Instrumental Tradeoffs

The distinction between instrumental and epistemic rationality is dramatic enough that I wonder if we should really be using the same word for both.

ETA: Just as I was posting this I came up with a response: The two variants might be well described as seeking correct knowledge and correct action respectively, with the common factor being correctness. So maybe using the same word plus a modifier does make sense.

ETA2: As army1987 points out below, I've just exhibited the same conflation I was concerned about. Embarrassing, but consider it evidence for my original point.

Lest you think the distinction between epistemic and instrumental is merely a theoretical possibility, consider the following anecdote.

Since sometime last year, I have been using PredictionBook to track my daily, weekly, monthly, and yearly goals (I stopped making them public after someone complained) in order to develop a large enough reference class to draw from when making business decisions (in order to eliminate the need for my "gut feeling" variable in my forecasting rule). Over the course of half-a-year I almost completely overcame my susceptibility to the planning fallacy (at least, in the domain of medium-term business plans).

Then, in February, my first son was born. I had badly underestimated the adjustments I would have to make to my routines (stupid, I know) and started failing lots of my goals. This caused my forecasts to show that I was probably going to fail massively on several important projects. If you remember your procrastination equation, this essentially tanked my expectancy, decimating my motivation. This started a failure spiral that I didn't recover from until only a few weeks ago (with the help of The Motivation Hacker).

Anyway, I think the take-away if this: yes, the outside view is very useful for accurately forecasting the future, but keep in mind that your psychological state is causually influenced by the very forecasts you make and this can easily lead to a self-fulfilling prophesy of failure.

Then again, you should take my analysis with a grain of salt. N=1 and all that.

The article seems quite incomplete without even mentioning value-of-information. Instrumental and epistemic rationality have the same goals when the VOI of learning things is positive, and opposite goals when the total VOI is negative. Now, it may be hard to capture the VOI of, say, movie spoilers and truths that are bad for you, but the typical piece of information is positive VOI. In other words, most information merely lets you make better choices, as opposed to influencing your experiences in a predicted-in-advance negative manner.

This is basically the entire reasoning for going on an information diet. Not all truths are of equal value to you, so if you can deliberately get only the high value truths, you're consistently better off.

Basic but necessary post.

Instrumental rationality is "systematized winning", epistemic rationality is not, and (often?/sometimes? - depending on your priorities and situation) quite the contrary.

There are also things which are bad to learn for epistemic rationality reasons.

Sampling bias is an obvious case of this. Suppose you want to learn about the demographics of city X. Maybe half of the Xians have black hair, and the other half have blue hair. If you are introduced to 5 blue-haired Xians but no black-haired Xians, you might infer that all or most Xians have blue hair. That is a pretty obvious case of sampling bias. I guess what I'm trying to get at is that learning a few true facts (Xian1 has blue hair, Xian2 has blue hair, ... , Xian5 has blue hair) may lead you to make incorrect inferences later on (all Xians have blue hair).

The example you give, of debating being harmful to epistemic rationality, seems comparable to sampling bias, because you only hear good arguments for one side of the debate. So you learn a bunch of correct facts supporting position X, but no facts supporting position Y. Thus, your knowledge has increased (seemingly helpful to epistemic rationality), but leads to incorrect inferences (actually bad for epistemic rationality).

There's also the question of what to learn. You could spend all day reading celebrity magazines, and this would give you an increase in knowledge, but reading a math textbook would probably give you a bigger increase in knowledge (not to mention an increase in skills). (Two length-n sets of facts can, of course, increase your knowledge a different amount. Information theory!)

Well, one obvious connection is that sufficient degree of epistemic rationality is a prerequisite for instrumental rationality (but not vice versa).

Basically, if you're looking for the shortest way from A to B (instrumental), you can't find it unless your map is correct (epistemic) { or you're incredibly lucky :-D }. So epistemic rationality is the foundation, base for the instrumental rationality.

One of the implications is that ceteris paribus it's better to sacrifice instrumental for epistemic rather than epistemic for instrumental.