Are you so sure?
If it is desirable to achieve compromises or overcome differences of opinion (and it most certainly is), then it would be far more suitable if we could explain which areas are gray zones in our thinking -- and why.
It says something unflattering about speakers of English that we don't have a better taxonomy for uncertainty. We have a language so rich that we can name 120 different colors of crayons. We have words that are abused senselessly, like "literally" and "absolutely" and "fundamentally", which speakers rarely mean...well, literally.
■ And yet, we don't have efficient ways of conveying uncertainty using our language. We don't have economical means of of saying, "I will know more when more information is available", or "I have low confidence in my reasoning because certain aspects are outside my expertise". Donald Rumsfeld's famous rant about "unknown unknowns" illustrates the problem well: It was superficially confusing because he had so few useful words at his disposal. In Rumsfeld's own words, "It sounds like a riddle. It isn't a riddle. It is a very serious, important matter."
■ English doesn't really offer gradations of uncertainty, either. Sure, we can be "pretty sure" or "fairly certain" or "almost positive" about things, but even those are unclear definitions. Given the survey results that say that people have widely ranging mathematical interpretations of words like "likely" and "unlikely", we need something much better than highly-disputed probabilistic words.
■ Vast portions of life are subject to uncertainty -- basically, anything other than "The Sun will rise in the east and set in the west". (And, even then, it's only exactly east or west twice a year. The rest of the time, it's a little north or south of due east or west.) In fact, it is a deep-seated problem if people find it easier to express unwarranted or exaggerated confidence than to explain the degree or source of their uncertainty.
■ People can barely wrap their brains around the basic vocabulary of mostly sunny or partly cloudy or "a mix of clouds and sun", much less use the language to express the same degrees of uncertainty or incomplete certitude about other aspects of life, both ordinary and extraordinary.
■ If it is desirable to achieve compromises or overcome differences of opinion (and it most certainly is), then it would be far more suitable if we could explain which areas are gray zones in our thinking -- and why -- so that we can express to others where we are subject to persuasion, seeking additional information, or withholding our certainly only to buy time to "sleep on it".
■ The depth of our vocabulary for a matter tends to indicate how seriously we take it. A sound, for instance, can be a whine, a whinny, a screech, a scream, a whistle, or a shriek -- all similar, but all clearly different. Yet there is no comparable depth of vocabulary for describing uncertainty. That's a real shame, because it leaves the ground wide open for people to express ever-increasing levels of certitude where none is warranted, when instead good faith would demand better explanations about those areas where we are uncertain.
■ This tendency causes us to surrender ever more of the discourse to those who are increasingly sure of themselves -- even though they often have diminishing reason for so being. This invites a dishonest form of intellectual warfare between opposing sides, which line up more out of tribal loyalty than out of reason, and it squeezes out those who hold unorthodox or heterodox views.
■ People can scarcely be expected to know the difference between instinct (which animals possess from birth), and intuition (which is speedy reasoning developed and honed from experience). Failing to know the difference even between these things, we can hardly expect people to appreciate the nuances of confidence. The closest we come is to offer people percentage odds of certainty, as in being "90% sure" of a thing. That we don't have simple words for expressing any of this better is a true shame.
■ We ought to have a linguistic construction comparable to "mostly cloudy" that expresses, "I don't know enough about this to be certain for the time being, but as soon as I have more detail I will have a reasonable opinion". We need a shorthand way similar to "a chance of showers" for expressing, "My past experience runs contrary but I don't know enough in this particular case to say what I think." Filling those gaps won't make everything perfect, but it might salvage our thinking and our debates from the corruption that comes from misappropriated confidence.