What are your rules of thumb?

by DataPacRat1 min read15th Feb 201376 comments


Personal Blog

I'm not as smart as I like to think I am. Knowing that, I've gotten into a habit of trying to work out as many general principles as I can ahead of time, so that when I actually need to think of something, I've already done as much of the work as I can.

What are your most useful cached thoughts?

A few of the rules-of-thumb I've already pre-cached include:

  • "Stay classy". Assume that whatever social interactions I have are going to come back to me in twenty years, so try not to make my future self too embarrassed; be as polite and respectful as feasible.
  • "The rule of threes: for anything important, try to have at least three sources, including at least one under your own control". Adapted from some wilderness survival books, it also applies to anything from home emergency kits to internet access to news sources.
  • "Assume I'm more likely than not going to get the worse side of the bargain." There are lots of people who are better than me at haggling, negotiating, and social sciences - in fact, I'm almost certainly somewhere down on the lower half of the bell-curve. So if it's possible to be taken advantage of in a deal, then I'm probably the one who's going to get taken advantage of.
  • "Assume I'm more likely than not going to get the worse side of the bargain." Applied to the field of ethics; if an ethical system says that it's moral to shoot someone for stealing an ice cream, then I assume that someone is going to mistake me for having stolen it and try to shoot me; or, if it's supposedly moral for a rich man to charge a thousand dollars for a bottle of water, I assume I'm going to be the one crawling in from the desert.
  • "It behooves every man who values liberty of conscience for himself, to resist invasions of it in the case of others: or their case may, by change of circumstances, become his own." I'm quite willing to steal ideas, including this phrasing of enlightened self-interest by Thomas Jefferson. (But I don't want this to become just another quotes thread.)


That should be a reasonable but not overwhelming sample of the sorts of ideas I mean, and am hoping to evoke more of with this post.


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Check boundary cases. Check extreme cases. Check trivial cases.

2Thomas8yAnd check the inverse case as well! Like "Hadn't I missed that plane, would there still be a midair collision? Maybe not."
2[anonymous]8yWhat's the difference between a boundary case and an extreme case?
2Alexei8yExample: testing a multiplayer game. Boundary cases: a game running with no players / max players. Extreme case: game running with a lot of lag and interference. Generalizing this to: boundary cases lie on some kind of natural boundary. Extreme cases are for things that don't have boundaries (e.g. you can always have more lag).
6Eugine_Nier8yAlso boundary cases aren't necessarily extreme, e.g., if you have some kind of optimizing buffer that kicks in when there are at least 10 players, 9 player and 10 players (and going from 9 to 10 and conversely) are boundary cases but not extreme cases.
0iDante8yI don't think there is one. At least not mathematically, which is where I do all these checks anyway. Solving PDEs ho!
1James_Miller8yI wonder how this works with dating?
3Luke_A_Somers8yExtreme cases and the trivial case (no SO) make sense and might be looking into. Not sure about 'boundary cases'.
6FiftyTwo8yAwkward "so are we a thing?" conversations.
2prase8yNot sure I want to know that.

Use the amount of unobvious subtleties involved in a subject you know very well to remind you of the unobvious subtleties that are probably present in the subject you don't know very well.

This is a great argument for learning some subject well regardless of what the subject is. A related point is that knowing a subject well exposes you to the idea of long inferential distances.

2Gimpness8yThanks for putting it far more eloquently then I my brain had

Personally: "Check you've taken your medication, exercised, eaten and slept sufficiently before giving bad feelings credence."

More generally, when considering a question "Always google it first."

I've recently added hydration to that first one.

I've come around to check for good lighting as well.

4[anonymous]8yThat's a good one, but I've sometimes overdone that, and ended up blaming my sleep deprivation/stress/mental fatigue/hunger/dehydration/drunkedness/the temperature/whatever for poor choices I've made (which doesn't usually explain why I erred in that particular direction, rather than any other possible one) as a rationalization to avoid dealing with the ugh field surrounding the actual reasons for my behaviour. All the variables that affect my mental performance aren't usually all at their optimal values at the same time, and I'd better deal with that.
0TrE8yAnd temperature.

The scope of the project is about right when what you're planning to do starts to feel too small, simple and narrow.

"There is nothing so useless as doing efficiently that which should not be done at all."

-- Peter Drucker, management consultant

In other words, when you're thinking about the best way to accomplish an unpleasant task, never forget that not doing it is an option, too.

When evaluating a [scientific] claim: Extraordinary claims require extraordinary evidence. This is basic Bayesianism, without the calculations. For example, if a preprint is called Solution to the cosmological constant problem, one glance at the abstract is sufficient to dismiss it with high confidence.

When designing software (or anything else): The cheapest, fastest, and most reliable components of a computer system are those that aren't there. Specifically, this means ruthlessly pruning my original design, until only the necessary functional parts remain. The Ideal Final Result approach is quite useful there.

When designing anything new: Build one to throw away, or at least be prepared to (sunk cost avoidance). This one is rather controversial, with people arguing that Agile Development/RAD make this unnecessary. However, if you notice how often a major OSS project is redesigned way late in the game because the original architectural and design decisions no longer apply, you might as well plan for it in advance.

Thanks for introducing me to the IFR. I now have a card (amongst many) on my bulletin board saying

"The ideal system -

  • Occupies no space
  • Weighs nothing
  • Takes no labor to implement
  • Requires no maintenance
  • Delivers benefit without harm

And most importantly

  • Does not exist"

If you constantly invent systems, this is a very useful reminder to ask yourself whether the system actually gives greater utility than it's encumbrance.

5John_Maxwell8yIt's interesting how the heuristic that makes you get better as a programmer/engineer (deliberately attack hard problems) is simultaneously a terrible one to apply when doing anything serious...
0Emile8yYep, though it becomes less surprising when you consider that if we didn't have any reason to attack hard problems, we wouldn't need a heuristic to tell us not to. We don't need a heuristic to remind us to not eat sand.
0savageorange8yProgramming, engineering, visual art, music, writing, it's all similar. You do a lot of studies where you capture things in intricate and intimate detail, but when you go to make a product for a purpose, that history of studying tells you what to leave out to build a harmonious and compelling system. Sculpture is probably a good metaphor for it. Something in my brain really wants me to bring up Sturgeon's Law [http://en.wikipedia.org/wiki/Sturgeon%27s_Law] here, so there it is :)

Being angry/upset/mad/panicked/fearful is a signal that:

I've probably done something wrong, and I have temporarily diminished reasoning abilities do to having entered flight-or-fight mode.

2savageorange8yI agree that reminding yourself that your reasoning powers have diminished as you become strongly emotional, is a useful measure. Needs clarification though. by "doing something wrong" do you mean 'thought something incorrect, self defeating, or unhelpful', or 'taken an action which is considered by others or society as "wrong"'? The former is true AFAICS (see Cognitive Behaviour Therapy). The latter is definitely not (no particular correlation, and can even occur when doing things that are considered good/ the right thing to do.). Whatever the case, currently it's rather open to the interpretation 'when I feel bad, I did something wrong'; a misapprehension that's all too common.
0James_Miller8y"doing something wrong" = didn't maximize my payoff.
2savageorange8yOn reflection, I have to disagree. Maximizing your payoff can equate to doing things that make you temporarily feel you're undergoing hell on earth*. If you don't accept this as normal, you are not maximizing/optimizing, but satisficing ('Do the thing that feels least wrong' just orbits your current habits and mindset) * Because humans aren't actually utilitarians or optimizing agents, of course. And because maximizing payoff usually (always?) requires some level of necessarily disturbing personal change.
4roryokane8yIndeed. To give an example, I currently have a bad habit of often being late for my first class of the day (in college). It’s a 50-minute long math lecture. When I’m late, I might arrive outside the classroom 15 minute after class has started. Standing outside, before I go in, I have an urge to skip the class entirely to avoid the embarassment of entering and sitting down in the middle of lecture, which would slightly disrupt class and draw the professor’s attention to my lateness. But when I gather my courage and enter anyway, I’m usually glad that I did, because I learn useful things in the remaining 35 minutes of class.
0eurg8yAlso, if you want to pick up such a signal, it is helpful that you are not totally overworked or tired, and also not under the influence of a significant amount of disinhibiting substances.

Mental cue in quotes.

"Have I googled this?" I still forget this one way too much.

Related: For any major life decision: "Have you put even 30 minutes of serious analysis and research into this?"

"Am I at the frontier?" as a reminder of the production possibility frontier whenever presented with ostensibly mutually exclusive choices.

"What does the marginal case look like?"

"SXD" a reminder of supply and demand in cases involving fungibility, what affects each in this case?

"behaviors, not goals" this helps fix a variety of errors in updating models of others and self.

"Am I/Are we/they being strategic?"

"TDT" a reminder that I will act similarly in all similar situations.

A literal rule of thumb.

0FiftyTwo8yCan you elaborate?
2RomeoStevens8yWhen deciding between more of X or more of Y, you can often get more of X and more of Y, and your framing them as mutually exclusive was false. Specific example: Should I be devoting more time to my personal project or to politics at work? Framing the choice this way implies a zero-sum relationship between them (+2 to work is -2 to personal project), but what is optimal might really be +1 to work, +1 to project, or even -1 to work +3 to project. So even if there is a tradeoff, it can be good to remind yourself that the tradeoff is not necessarily 1-to-1. This is also related to figuring out what you really want. Say you were deciding between two colleges or jobs. You should make sure that any potential tradeoffs when comparing their pros and cons are real, e.g. job A has benefits that sound good in far mode but you don't actually care about in near mode.

"If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack."

[-][anonymous]8y 12

If you're trying to do something you've never done before, and it involves multiple steps, something will go wrong.

Nobody is stupid, nobody is evil, and everyone is crazy.

What domains of knowledge are relevant to what I'm trying to do? Am I a domain expert? (The answer is almost always "no," but the point of asking this question is to emphasize that so I can't conveniently forget it.) If not, who are the domain experts? How do I find domain experts who could offer useful advice? Do the domain experts in this domain generally agree with each other, or is there substantial controversy, and if so, why?

5Eugine_Nier8yAlso, are the so called "domain experts" quacks?

Distrust any claim or story that is entertaining enough to be passed on based on its entertainment value alone.

Apply mental force to the problem. Amount and quality of thinking time seriously affects results.

I am often in situations where there would be a good result even if I did many stupid things. Recognize that success in those situation does not predict future success in more difficult situations.

Do the heavy lifting your own self.

Be willing to be right, even in the face of serious skepticism. [My father told me a story when I was a kid: In a parade, everyone was marching in line except one guy who was six feet to the right. His mother yelled, "Look, my... (read more)

0handoflixue8yCan you elaborate on that one?
2JRMayne8ySure. I ended up killing about a paragraph on this subject in my original post. The basic default to getting anything done is, "I do it." There are always delegable tasks, but even in unfamiliar harder situations I'll consult others then do it myself. A corollary of this is, "Own all of your own results." If you delegate a task, and that task is done badly, view it as your fault - you didn't ask the right question, or the person was untrained, or the person was the wrong person to ask. If you do the hard thing that needs doing, it will be easier to do that thing next time, and you'll develop expertise. Doing the work yourself does not mean going without advice; people who have been there before can be very helpful (sometimes as object lessons in what not to do.) Hope that's helpful.
0handoflixue8yWould it be fair to say you prefer self-sufficiency over delegation whenever it's reasonable?
[-][anonymous]8y 9

"Find a list or taxonomy"

For example, if you want to write comprehensively on the topic of societal problems, you might look at lists of industrial sectors, the titles and subtitles of the U.S Legal code, or a typology of crimes.

This is a very cheap way to crowdsource the availability heursitic, and to appear somewhat useful without having having any unique perspectives or good solutions.

[This comment is no longer endorsed by its author]Reply

Before I get a tattoo, I have to have continuously liked a design for a full year. This hasn't happened yet so I'm ink free, but it has been a year since I decided I wanted to get magnetic finger implants so I'm moving forward with that.

Other rule of thumb I use a lot: most times, the wrong decision is better than no decision than all.

If some step of a process which you expect to repeat can be automated, automate it, even if this takes ten times longer than just doing it "by hand."

When consistently applied over a long period of time, you eventually end up with webs of interlocking automatic steps which allow you to not only do the impossible, but iterate on the impossible a couple of times to make it look cleaner.

"Try to make it better." This is to counteract my tendency, when in conflict with someone, to default to the goal "Make myself seem right and make the other person feel bad." Which, if I stop and think about it, is never what I actually want.

Try to ask two questions every so often:

  • Is what I'm doing useful (including enjoyable)?
  • Is there a better way I could be doing what I'm doing?

If my inhibitions regarding a certain course of action seem entirely internal, go through with it because I'm probably limiting my options for no good reason.

I think staying classy can be taken too far if you're not careful. Sometimes doing slightly embarrassing or vulnerable things helps you build connections with trustworthy people. Sometimes, it just can't be helped. I'd say worry about being kind and respectful, but don't worry too much about things like ... crying or puking. They're not particularly classy, but not a big deal either.

0handoflixue8yMost social groups I'm part of would consider puking to be a serious failure of self control. Most of the male-dominated groups I've been in would view crying the same way. I think that one is really "know your audience".
5jooyous8yUnfortunately, I would argue that what you describe is a negative property of the groups you hang out with, and that your efforts would be better spent developing strategies for displaying tolerance when someone inevitably pukes or cries in order to start changing these group attitudes rather than ... training your body to never puke or cry.
1handoflixue8yI wouldn't disagree with you. That doesn't mean it's worth the effort to try and change their behavior, or to seek out new groups. I do have a "core" social group that is quite tolerant, and that works fine for me. It is also nice having social spaces where crying is abnormal, since then there's no pressure to engage in such displays. Thanks to an abusive father, crying in front of other people is extremely difficult, and I've only cried in public twice in my life. In other words, my body comes pre-trained to stoicism, and I'm still in the process of training myself to have the option to cry :)
2jooyous8yOh man, I kinda know that feeling. I'm so sorry you had to go through that. I guess I agree that sometimes it isn't worth trying to change the group's behavior, but sometimes it's not worth it to try really hard to avoid crying or puking either? Like, expending X amount of effort to avoid crying or puking isn't worth it if you can use any Y < X effort telling the group to stop being jerks about it. And maybe repairing puke damage, etc. Mainly I'm just arguing that crying and puking shouldn't be included in the "stay classy" heuristic and deserve their own cost-benefit analysis. Factoring them into that heuristic may lead to a lot of wasted effort and stress. Also, sometimes puking happens for a really good reason! I once accidentally drank moldy water and I puked like 30 minutes after. =/ I was really impressed! I guess we're more optimized for unpoisoning ourselves than for un-carpal-tunneling ourselves.
1handoflixue8yI wouldn't refrain from puking if I needed to, since it generally means my body is unpoisoning itself, but I WANT to avoid situations where I need to (i.e. don't go out if I have the flu, don't do six shots on an empty stomach) If it's important to you to cry, find an audience that's okay with it. I don't see this as a special case - if you dislike suits, don't hang around with people who consider jeans and a t-shirt to be insultingly under-dressed :) The heuristic "never cry or puke" seems bad, but so does "assume there's no social consequences to it". I can't think of a catchy way to put it, but I'd suggest that one should stay classy vis-a-vis the social group one is currently interacting with and, if that doesn't meet your needs, either change the group or move to a new one. I think a lot of "failure stories" in life stem from getting stuck in a group that isn't nurturing to what you want from yourself. It's also important to remember you can have multiple group memberships, and be different people to each group. Not every group you're in needs to meet your every need (at a minimum, this makes employment much more palatable :))
2jooyous8yI think we've converged to the "know your audience" heuristic. Or maybe "stay classy, for a context-sensitive definition of classy." Snappy phrases are hard. =] I agree with being aware of social consequences, but I also feel like some social consequences are crappy and need to be changed. And sometimes there is value in speaking up even if it doesn't directly change anyone's mind. They can learn to not do crappy things around me, because I will cause social consequences for them. T_T Generally, I wish it were more socially acceptable to listen to the person doing the weird thing. For example, it's generally acceptable to make a big deal about a person who is crying. Even the groups that are tolerant to crying will respond with a flurry of fussiness even when the person is saying "please ignore me, I'm okay." A lot of these things would be much easier if we could just cry or puke and count on everyone else to respond the way we tell them to respond. Because my post-crying, post-puking needs might be different than the next person's. Bah!
1handoflixue8yVery much agreed, and that's a lot of what I strive for in my own behavior. I've found a few people pick up on it, too, which is always pleasing to see little ripples of change.

Don't make an effort to be clever until you know that being naive won't be sufficient.

Arguments can prove too much as well as too little.

Selection bias doesn't explain everything, but it explains more than it seems like it should!

I notice an annoying empirical regularity. (The films I want to see at the cinema are the ones most likely to be sold out. Buses take too long to arrive, and when they do they come in twos or threes. Things go wrong most often when I'm trying to get something done in a hurry.) Chances are it's neither coincidence, nor reality magically conspiring against me — instead there's usually some mundane, obvious-in-hindsig... (read more)

-Hanlon's razor - I always start from the assumption that people seek the happiness of others once their own basic needs are met, then go from there. Helps me avoid the "rich people/fanatics/foreigners/etc are trying to kill us all [because they're purely evil and nonhuman]" conspiracies.

-"What would happen if I apply x a huge amount of times?" - taking things to the absurd level help expose the trend and is one of my favourite heuristics. Yes, it ignores the middle of the function, but more often than not, the value at x->infinity is all that matters. And when it isn't, the middle tends to be obvious anyway.

A good way to find flaws in arguments: Take the argument to it's logical extreme, this likely results in an absurd conclusion. Now figure out why this conclusion is absurd and see if the same problem applies to the argument in the case under consideration.

When considering an abstract argument, it helps to keep a concrete example in mind.

Criticism is not censorship. (It's amazing how many flame wars seem to occur because the participants can't make this distinction.)

  • If something sounds certainly correct, check it up on Wikipedia anyway - it takes less than a minute. Likewise if it sounds almost certainly wrong.
  • If I don't know why exactly someone went to his conclusion, do not assume he thinks it for the wrong reasons.
  • If I can predict I will be too busy to go to gym in the next few days, do a 5-minute (1-set) exercise - this is at least 50% of the efficiency of a normal exercise.
  • When I feel the drive to argue, do careful judgement on whether it's efficient to do so.
  • Never blame people for their biases. If they don'
... (read more)

Assume that whatever social interactions I have are going to come back to me in twenty years, so try not to make my future self too embarrassed; be as polite and respectful as feasible.

This is true but tricky; Many of the behaviours that I have previously thought of as polite or respectful I've later learnt come off as detached, dismissive, or abrupt. And asking people about what politeness or respect means to them is surprisingly uninformative.

So I personally find this useful only once it's simplified to essentially Right Intent -- ie. act out of inte... (read more)

From lessons I learned in HPMOR before making an important decision ask yourself "What do you think you know, and why do you think you know it?" I have found that this not only shows you what knowledge you have is sound enough to make decisions on but shows which pieces of knowledge you're emotionally attached to and would therefore lead to a biased conclusion.

[-][anonymous]8y 1

The first and foremost rule of thumb that I follow is 'question everything'. I find it easy to apply and it has yielded positive results.

needs a loop breaking clause, otherwise you spend all day in bed in a state of existential angst. Or at least I do...

8James_Miller8yPlus attention is a scarce resource.
4OrphanWilde8y"...but question data last." is the necessary addition for my rule of thumb. The vast majority of the time that the conclusion is wrong, the conclusion didn't follow from the data supposedly used in evidence of it anyways.
[-][anonymous]8y 0

My ignorance and capacity for error are unending, but through great effort and feedback from others I sometimes may learn from my mistakes and make new mistakes next time.

0Eneasz8yAlways Try To Be Less Wrong? :)
3RomeoStevens8y"Always make new mistakes" -Esther Dyson has this appeared in a rationality quotes thread already?
2NancyLebovitz8yHave you googled it?
0RomeoStevens8yYup, couldn't find it. I wasn't sure how reliable an indicator that was in this case.
0NancyLebovitz8yI tried the quote in the search window for the site, and the only hit was your mention here. I consider that good evidence that it hasn't been cited in a quotes thread.
0RomeoStevens8ydoh! forgot the "site:" modifier existed.