A sociologist reports that 90% of people in a given society keep their promises. Which conclusion can be legitimately drawn from this finding alone?
APromise-keeping is morally required in that society, since it reflects the community's actual norms
BPeople in that society probably feel some obligation to keep promises
CPromise-keeping is statistically common in that society — and nothing more
DIt is morally permissible to keep promises in that society
The is-ought gap (Hume's guillotine) holds that no purely descriptive premise entails a normative conclusion by itself. 'Most people do X' is a descriptive claim about behavior; it tells you nothing on its own about whether people ought to do X. You need an independent normative premise to bridge the gap. Option A commits the fallacy directly. Option B goes beyond the data — the survey records behavior, not felt obligation. Option D smuggles in a normative claim (permissibility) that the descriptive data cannot support.
Question 2 Multiple Choice
Which of the following is a categorical normative claim rather than a hypothetical one?
AIf you want a good reputation, you ought to tell the truth
BIf you aim to maximize your income, you ought to invest early
CYou ought not to break a promise, even if no one would ever know
DIf you care about fairness, you ought to give people equal opportunities
A hypothetical normative claim takes the form 'if you want X, you ought to do Y' — the obligation is conditional on a desire or goal. A categorical claim holds regardless of what anyone wants. 'You ought not to break a promise, even if no one would ever know' is categorical because it makes no reference to the agent's desires or goals — it applies unconditionally. The other options are all explicitly conditional on having particular desires (reputation, income, fairness-commitment).
Question 3 True / False
If you morally ought to do something, that obligation applies even if you do not want to do it and would not benefit from doing it.
TTrue
FFalse
Answer: True
This is the categorical character of moral obligations — one of the key features that distinguishes normative 'ought' from mere advice or prediction. Unlike hypothetical imperatives ('if you want X, do Y'), moral obligations are not voided by the absence of a relevant desire or benefit. 'You ought to keep your promises' does not come with an implicit 'unless you don't feel like it.' If it did, it would function as a hypothetical imperative, not a moral obligation. This is what makes moral claims distinctively demanding.
Question 4 True / False
Since acting naturally is common to most humans, we can conclude from this fact alone that acting naturally is morally required.
TTrue
FFalse
Answer: False
This is a textbook is-ought fallacy. 'Acting naturally is common' is a descriptive claim; 'it is morally required' is a normative claim. You cannot derive the normative conclusion from the descriptive premise without adding an independent normative principle (e.g., 'what is natural ought to be done'). The is-ought gap means no amount of factual evidence about what is natural, common, or evolutionarily adaptive can, by itself, establish a moral obligation. The additional normative premise needs independent justification.
Question 5 Short Answer
Explain why the observation that 'most people sometimes lie' does not, by itself, establish that lying is morally permissible.
Think about your answer, then reveal below.
Model answer: Descriptive claims about what people do cannot, without additional normative premises, establish what people ought or are permitted to do. 'Most people lie sometimes' is a fact about behavior; 'lying is permissible' is a normative claim about what standards allow. To get from the first to the second, you need a bridging premise — such as 'whatever most people do is permissible' — which is itself a normative claim requiring justification. The is-ought gap ensures that facts about the world never entail normative conclusions on their own.
This is Hume's guillotine in action. No pile of descriptive premises — however large — produces a normative conclusion without a normative input somewhere. 'Most people lie' describes the world. 'Lying is permissible' makes a claim about what standards allow. These are different kinds of statements. Closing the gap requires a normative premise, and that premise cannot itself be derived from pure description. This is one of the foundational constraints on ethical reasoning: you can't get 'ought' from 'is.'