Letter (Astounding, September 1938): Crows Can Visualize Up to Four—and That's Man's Limit of Visualization. But Man Can Count—Whereby He Excels the Crow.
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Overview:
Editions/Publications:
- Unknown. Astounding Science-Fiction, September 1938 (Unknown, Jim Blish, Street & Smith Publications, Inc., $0.20, 164 pages, pulp, MAGAZINE)