Science and public issues
| English | Chinese | Pinyin |
|---|---|---|
| risk | 风险 | fēng xiǎn |
| communicating uncertainty | 传达不确定性 | chuán dá bù què dìng xìng |
Evidence does not settle a value question
- Science can say what a policy would do. It cannot say whether it should be done.
- "The vaccine reduces transmission by X%" is a measurement. "It should be mandatory" is a value judgement.
- A strong answer says which of the two it is making, and most weak answers slide from the first into the second without noticing.
Which statement is a value judgement rather than a measurement?
Science can say what a policy would do. Whether it should be done is a different kind of question.
Risk
- Risk 风险 combines how likely harm is with how bad it would be.
- Public argument routinely confuses the two: a rare, dramatic harm feels larger than a common, mundane one.
- ⚠ A risk is also always relative to an alternative. "Is X safe?" is unanswerable; "is X safer than Y?" can be answered.
Assessing a risk properly needs which of these? Choose all that apply.
"Is X safe?" is unanswerable; "is X safer than Y?" can be answered.
Communicating uncertainty
- Communicating uncertainty 传达不确定性 is a skill: a range with a confidence level says more than a single number.
- A journalist wants one number. Giving one without its range is how a careful finding becomes an overstated headline.
- Say what would change your mind. It is the clearest signal that a claim is scientific rather than positional.
Rewrite "is this water safe to drink?" as a question science can answer.
Example: "Are the lead and bacteria levels in this water below the national drinking-water limits?"
Two ways to report the same finding.
Single number: "The treatment cuts recovery time by 3 days."
With uncertainty: "The treatment cut recovery time by about 3 days, with a range of 1 to 5 days across trials. The effect was smaller in older patients, and the longest trial ran only six months."
The second is what the data supports. It is longer, harder to headline, and it is the version that will still be true in a year.
Which report of a finding is the one still true in a year?
It is longer and harder to headline, and it is what the data actually supports.
"Is it safe?" is not a scientific question. "How likely is this harm, how serious is it, and compared with what alternative?" is three scientific questions, and answering those is what the unit is training.
Do not use the existence of uncertainty as a reason to dismiss a finding. Every measurement has a range, and a result with a stated uncertainty is stronger evidence than one presented as a single exact number — not weaker.
A result reported with an uncertainty range is weaker evidence than one given as a single number.
It is stronger. Every measurement has a range; hiding it does not remove it.