Sometimes a writer has no choice but to hedge a statement. Better still, the writer can qualify the statement—that is, spell out the circumstances in which it does not hold rather than leaving himself an escape hatch or being coy as to whether he really means it. If there is a reasonable chance that readers will misinterpret a statistical tendency as an absolute law, a responsible writer will anticipate the oversight and qualify the generalization accordingly. Pronouncements like “Democracies don’t fight wars,” “Men are better than women at geometry problems,” and “Eating broccoli prevents cancer” do not do justice to the reality that those phenomena consist at most of small differences in the means of two overlapping bell curves. Since there are serious consequences to misinterpreting those statements as absolute laws, a responsible writer should insert a qualifier like on average or all things being equal, together with slightly or somewhat. Best of all is to convey the magnitude of the effect and the degree of certainty explicitly, in unhedged statements such as “During the 20th century, democracies were half as likely to go to war with one another as autocracies were.” It’s not that good writers never hedge their claims. It’s that their hedging is a choice, not a tic.

-- Steven Pinker, Why Academics Stink at Writing (Behind Paywall)

I picked up the folders for the two courses required of every student at the school. Statistics and epidemiology. Epi—what?

In the first lecture, we ‘reviewed’ all the major study types. For example, in the case-control study you find a group of people with a disease, and then look for people who are much the same but without the disease. You compare the two groups to see if they have different risks. It’s a relatively cheap method, but it doesn’t tell you much about the order in which things happen. I can’t remember all the examples used in the lecture, but let’s say you want to look at causes of depression in women. You start with 600 depressed women, find another 600 who match them in age, ethnicity and educational status, and then ask them all about their lives. Let’s say you find out that women who are depressed are six times more likely not to have had sex in the last year as women who are cheerful. That means if you’re not having sex you get depressed, right? But hang on, couldn’t it be that women who are moping around looking miserable don’t get laid much?

Perhaps you’d be better off with a cohort study. You start off with several thousand women who are perfectly happy. Then you follow them over time, recording their behaviours, and see which of them get depressed. If you find that women who have sex are less likely to become depressed than women who aren’t getting any, it suggests it is the lack of sex that causes the depression, not the depression which stops you getting laid. You can throw out the ‘misery guts’ theory and recommend more good sex as an intervention to promote mental health.

-- Elizabeth Pisani, The Wisdom of Whores, p. 16

The terror that took Baru came from the deepest part of her soul. It was a terror particular to her, a fundamental concern—the apocalyptic possibility that the world simply did not permit plans, that it worked in chaotic and unmasterable ways, that one single stroke of fortune, one well-aimed bowshot by a man she had never met, could bring total disaster. The fear that the basic logic she used to negotiate the world was a lie.

Seth Dickinson, The Traitor Baru Cormorant, p. 292

Your tactics are self-centered. You have forgotten that you are not the only player on the board, that inherent talent speaks for no more than experience, and that others around you seek to expand their authority and constrain yours. Your error is fundamental to the human psyche: you have allowed yourself to believe that others are mechanisms, static and solvable, whereas you are an agent.

Purity Cartone, in The Traitor Baru Cormorant by Seth Dickinson, p. 180