Movement or shift?
Two similar phrases describe different changes.
- 01
Quantity demanded → a point
The amount buyers would purchase at one price. A change in the good’s own price means movement along the curve, other things equal.
- 02
Demand → the relationship
Income, preferences, or related prices can shift the curve. More income increases demand for a normal good; that qualification matters.
- 03
An extra example to check
A coffee price cut changes quantity demanded. A change in buyers’ preferences for coffee can change demand. This example illustrates the distinction; it is not a quote from the excerpt.
CHECK YOUR UNDERSTANDINGWhat would you label a change in the good’s own price?
A movement along the demand curve, holding other factors constant. The curve itself does not shift just because the good’s own price changes.
