Compare causes without rerunning the past

Why did two similar towns respond differently to a shortage?

Context and mechanism

Historical causes operate at different scales. A harvest failure can trigger an immediate shortage, while land ownership, transport access and rules for distributing grain shape who becomes hungry. A trigger explains timing; a structural condition helps explain vulnerability. Naming both is more useful than choosing a single cause simply because it came first.

Comparison tests an explanation by examining cases that share some conditions and differ in others. It is not a laboratory experiment: towns also differ in unrecorded ways. Choose cases because they bear on your question, not only because they produce the desired result. Ask whether the same mechanism could operate in both places and what evidence would show its operation.

Counterfactual reasoning asks what might have happened if a condition had differed. It can clarify a causal claim but cannot authenticate an alternate past. A numerical classroom scenario may hold all other variables constant; historical conditions rarely permit that. State which assumptions make a comparison useful and which limit its strength.

Work through the evidence

Fictional Town A and Town B both lose one fifth of their harvest. A has a public grain reserve; B does not. A reports fewer hunger complaints, but A also has a navigable river. The reserve is a plausible explanation, not an isolated cause. Delivery records could help distinguish stored grain from new imports.

Your investigation

Construct a chain from harvest loss to household shortage. Add reserve distribution, imports and complaint recording as separate branches. Identify a record that would distinguish two explanations.

Sources and their limits

Paired town dossier

Both towns lose 20% of harvest. A has a reserve and river access. B has neither.

Fictional comparison with two changing conditions; deliberately not a controlled experiment.

Complaint registers

A records fewer complaints than B. The two offices use different registration hours.

Fictional reporting process can influence observed complaints independently of hunger.

Extend and revise

High school: Build a cause-and-consequence diagram with at least one rival explanation.

AP practice: Write a claim weighing the relative importance of two causes with concrete evidence.

Introductory college: Justify case selection and identify evidence that could falsify the proposed mechanism.

Which part of your argument explains timing, and which explains unequal consequences?