Canon of proportion — where it appears
Named by 2 essays across one field — each of them below, with the objects they name alongside it.
Assembled from several views
An Egyptian relief takes each part of a figure from the direction that identifies it — head in profile, eye and shoulders frontal, a pond in plan. What that buys is exactly measurable: any single viewing direction keeps at most √k of k perpendicular aspects, so the best compromise view retains 58% of each.
A grid on the wall is a scale without a projection
An Egyptian canon rules a wall into squares and counts a figure's height against the ruling — no horizon, no centre, and a length recovered to 1.4e-14% of error where the same reading taken off a pinhole misses by 58%. Applied instead to a pinhole picture, the furthest of six equal figures reads at 19% of its true height.
Named alongside it
The objects these essays reach for when they reach for this one.
Drawing systemArea scaleAspectivecentre of projectionCountingDemonstrationDrawing conventionForeshorteningIdentifiabilityIsometricMeasuring pointOcclusion