The Georgia Negro: A Social Study - Diagram shows two maps of the United States, one showing state in which African Americans born in Georgia reside in 1890 and the other showing where African Americans living in Georgia in 1890 were born [LCCN2013650427]
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 mirrored pair is the mechanism: the same map twice with the question reversed, so the reader performs the subtraction and reaches the conclusion themselves rather than being told it. Reserving black for Georgia and colour-as-separation for everything else gives the sheet a single fixed point the eye returns to in both panels. The arrows carry numbers as small as single digits, and that tininess against a six-figure black shape is the argument - the scale difference is felt, not computed.
Steal this when
Use this when you want to kill a churn or leakage narrative by showing that movement is trivial next to the retained base. Run the same visual twice with the direction flipped and keep the anchor figure identical in both frames.