Users of languages improve them by adding new words. Often languages would also be improved by taking away words – not so much such that nobody ever uses the word, but just so it is not necessary to convey a certain meaning. For instance since it is very rare for a claim to be meant with one hundred percent certainty, it would be more efficient if a speaker had to add ‘certainly’ in that case, rather than adding ‘probably’ or ‘I think’ for every other case where they are only claiming a best guess.
Robin Hanson explains the retention of such extra words by people being stuck in a signaling game: if you don’t add the extra words in the normal cases, then people mistake you for those who really are making extreme claims, since everyone else adds the extra words when they are making the ordinary claim.
That seems correct. But why would this begin? How did everyone ever come to use the long, complicated sentences for saying ordinary things and the succinct ones for claims that almost nobody ever wants to make? Perhaps we just especially notice the half of times when the signals are assigned the inconvenient way around?
Another plausible theory is that the usual cases are complicated, whereas simple cases are unusual and extreme. Adding qualifications allows you to say something much more specific and nuanced. And we usually want to refer to specific, nuanced state of affairs. However for uncontroversial issues nobody seems to have much trouble interpreting simple statements as the obvious more complex ones. If you say ‘roofs in England have steeper slopes than roofs in Australia’ most people would interpret this as indicating some sort of general tendency for steeper roofs in England. If you want to say the extreme thing, you have to say something like ‘literally every roof in England is steeper than every roof in Australia – no, I mean it literally. I know, it sounds insane! Look, I’ll send you these seven review articles summarizing the research.’ Whereas if a person says ‘women are less interested in engineering than men’, listeners seem to often interpret this in such a way as to make raising counterexamples a reasonable response.
So it seems closely connected with controversy. It appears that people making uncontroversial claims are much more scared of being misunderstood and thought controversial than people making controversial claims are the opposite. Or at least they are willing to pay more to avoid being misunderstood. So the controversial people can snap up the short, efficient signals without worrying about confusion, leaving the uncontroversial people to run away to awkward, qualified corners of signal space.
But it’s not obvious why uncontroversial people should be more afraid. The probability of misunderstanding seems to be much lower for them, because there are so few controversial people. A random apparently extreme claim is much more likely to be an error of speech than a random apparently moderate claim is. So to make the risk from potential misunderstandings higher for people making moderate claims, the cost of being misunderstood needs to be a lot higher for them. Why would this be?
Honesty
One answer is that more controversial claims are just more costly to make – everyone would prefer to make non-controversial claims, but some people are forced to make controversial claims by honesty. If they are misunderstood, all the better for them. This seems to have an element of truth, but doesn’t account for the apparent glee many people exhibit while making controversial claims.
Taking back
Another thing you might wonder about such models is why anybody should be much worried, given the possibility of clarification. Nobody fears being too misunderstood about roofs, in part because if the audience appears to be taking the statement the wrong way, it is cheap to clarify. Most conversation seems to involve plenty of this. Yet it seems to me at least that if you say something apparently controversial you are much less allowed to take it back than if you say something non-controversial. The audience is suspicious. Perhaps your slip of the tongue is taken as telling, regardless of your conscious corrections. Whereas saying something uncontroversial first is not taken as much of a sign about you. If you correct your non-controversial statement to a controversial one, listeners are generally willing to allow that you are controversial.
Selection
Another possibility is that people are basically selected into making extreme claims or not according to whether they are terrified of other people criticizing them. Naturally the uncontroversial people are more scared of being misunderstood as controversial because this is what being uncontroversial is about.
Signaling
When talking about controversial topics, your words are taken as a sign of what side you are on. Perhaps to show that you are on the side considered more virtuous, you need to pay higher costs. People who believe controversial things might prefer to look like those who don’t, but their lack of passion for the cause means they can’t be bothered adding all the qualifiers, or feel more uncomfortable doing so. The people who truly believe the ‘virtuous’ claims can be bothered, and do so to set themselves apart.
This would also explain why listeners wouldn’t allow you to take back controversial sounding claims – if you could say things cheaply and only elaborate when you were caught, it would be much cheaper, so may not signal your devotion correctly.
It doesn’t however explain why you would have to do this particular costly act, instead of some other. But that is rarely explained I think.
Status
I discussed this with Robin, and he suggested a status explanation: making controversial claims is generally a bid for status. If roofs were controversial, then by claiming that roofs in Britain are steeper than roofs in Australia, you are taking the initiative to ally your group with ideas that the current powers consider enemy. So you are making a bid to increase your own importance in the group, as well as trying to change the status of other groups and ideas. People respond strongly to bids of status. If you want to do something that looks a bit like a bid for status without being beaten down into your place by all around, you have to do some sort of accepted submission dance at the same time to make it not like a bid for status. This seems intuitively somewhat plausible, but leaves even more questions unanswered: why does this behavior convince people around you that you are not bidding for status? Why doesn’t clarifying later work? Why are you so aggressively interpreted as bidding for status anyway, instead of making the nearest probable, non-controversial claim?
Responses
What to do about this? One intuitive possibility is to replace words instead of just removing some. For instance we could introduce the usage:
Qualifiedly: with all due qualifications, and some more
Then instead of saying ‘he sometimes seems a bit silly, to me, but I might just be biased, and I don’t really know him that well, and I’m sure we all have different preferences anyway, and that might be relevant..’ you could just say ‘he seems qualifiedly a bit silly’.
I’m not sure if this would work in any of the above models though. It probably won’t work if the point is to pay a cost, or do a special dance. In the signaling case there is probably no way out, unless non-controversial people can find a cheaper way to set themselves apart, that is still expensive enough to keep out the controversial people.
If the important thing is just to say something that can’t be interpreted badly the first time, something like this has a better chance of working.
Turning it around, how you expect such a change of words to go says something about which theory of inefficient qualifications is correct.
Meteuphoric 
It’s worth distinguishing two flavors of “certainty”:
1. Epistemological certainty–your mental model of reality does not allow for any other possibilities. Arguably this requires a lack of education and/or imagination.
2. Operational certainty–other possibilities exist, but you don’t believe they are worth accounting for until something surprising happens. Or you have actually prepared some plans for them, but you don’t think it’s worth the trouble of communicating them in advance; I’m not very sympathetic to this sort of attitude in the context of today’s information and communication technologies, but I realize it has sometimes been justifiable. An analogy can be made between the second scenario and use of exceptions in computer programming.
Outside of academics, immediate effectiveness is usually more important than abstract accuracy. I claim that operational certainty is common enough to make existing linguistic conventions reasonable.
Also related: Scott Adams’s “BOCTAOE” qualifier.
The “qualifiedly” approach doesn’t work at all. I can’t tell what the person was actually trying to say, and some qualifiers are much bigger disclaimers than others. I’d be forced to conservatively assume an interpretation like “he seems a bit silly unless he doesn’t”.
Epicycles. See also Gould, Spandrels of San Marcos and the Panglossian paradigm. Are you explaining pattern or fitting noise?
I think that qualifiers are mostly about signalling willingness to back down if challenged. This alone is sufficient to determine the direction the qualifiers go in! Consider what happens if you’re optimizing for time. In that case, you both omit the qualifiers (they slow down communication), and you’re also less willing to accept challenges. Consider political slogans, which are subject to some of the strongest length-reducing pressures of any use of language.
If this is how most people are using these words, then it creates a singificant risk of miscommunication between geekier types (to whom the qualifiers have semantic content) and more ordinary types (to whom they don’t). It might also explain the signaling backlash that comes up when people try to use probabilities like 0.5 instead of weasel words: the semantics and the grammar tell opposite stories about whether the point can be challenged.
Katja,
The shorter sentence is assigned to the unqualified assertion because a shorter expression is more emphatic–for reasons explained by construal-level theory. (See Emphasis by brevity of sentences, paragraphs, and sections — http://tinyurl.com/al8ruo5 )
jimrandomh,
Is it more important to signal you will back down if challenged than to signal you won’t?
People want to convince listeners – that’s why “researchers” with no evidence preface their claims with “absolutely” on Radio 4. Often modifiers are added not to admit frailty, but to diffuse attention from it. So you get “we can’t easily generalise” when the truth is “we can’t generalise”.
Without knowing our destination, however, we can ensure we are travelling toward it by comparing causal theories.
“That seems correct. But why would this begin? How did everyone ever come to use the long, complicated sentences for saying ordinary things and the succinct ones for claims that almost nobody ever wants to make?”
I think you have a biased sample of “almost everybody”, and many more people than you realize /do/ believe ridiculous extreme claims.
Late to the thread, but I’m surprised no-one has made any comment about listener interpretation.
If you say something short assuming that others will give you the benefit of assumed qualifiers, you are at the mercy of others’ rhetorical goals. In one-on-one speech, later clarification might be sufficient. The worrying case is when your remark will be used in a situation where you cannot clarify.
Basically, I think it comes down to whether you are willing to assume goodwill and common goals in all those who might repeat your statement.