The Georgia Negro: A Social Study - Map shows the location of residences of different classes of African Americans and the location of residences of whites [LCCN2013650363]
The pattern
This still is filed under Data as proof.
Define
A chart, map, or count that is the argument, not an illustration next to the argument.
Mechanism
Sighted evidence. The reader is asked to believe their eyes: a bar, a share, a spread on a map.
Verdict
The claim is comparative or quantitative and the figure can be read without a caption doing the sell.
Why it works
The unit of the mark is one household, so the map shows density and composition at the same time without any aggregation the viewer has to trust. Colour encodes social class rather than race, which forces the European viewer to read internal differentiation instead of a single category. Placing the legend inside an empty corner of the map instead of outside it makes the framing facts - total area, acres owned - read as part of the territory. Because the physical geography is drawn in one pale wash and nothing else, the dots are the only saturated thing on the sheet and the settlement pattern reads instantly.
Steal this when
Use this when an aggregate statistic about a population is being used against it and the honest rebuttal is granularity - map one dot per unit, colour by the dimension the aggregate hides, and put the framing totals inside the map's own empty space.