The donor grows only in the West

Claim (verbatim)

The donor grows only in the West. Donor portraiture is one genre under two theologies of presence. Latin donation imagery kept renegotiating scale as lay patronage broadened and purgatorial accounting personalized the stakes; the Byzantine proskynesis format was liturgically frozen. The handbook impression that donors get bigger is not the claim — the claim is the divergence: a dated, monotone Latin growth curve with a specific crossing point, against a Byzantine flat line over the same centuries.

Prediction clause (verbatim)

Primary clause (the verdict follows it, requiring both arms): measured on at least 100 dated Latin and 50 dated Byzantine donor images, the Latin donor-to-holy-figure height ratio shows a positive secular trend whose decadal median crosses 0.85 between 1380 and 1440, while the Byzantine trend over 1100-1450 is statistically indistinguishable from zero, the median ratio staying within plus or minus 0.05 of its twelfth-century value.

Kill-dataset (verbatim)

Kill: the Index of Medieval Art donor-image records with dates, measured on British Library, BnF, and e-codices digitizations.

Novelty / leakage triage

provisional — model-triaged, shepherd review pending

A provisional first pass authored by the model (Opus), not yet confirmed by the shepherd. It carries the same dated-search requirements as an authoritative verdict but is excluded from every headline figure and cannot underwrite a prediction until a shepherd confirms it. Provisional reading: Adjacent (closely related prior work exists).

Both arms are separately documented: the growth of Latin donor scale as lay patronage broadened is a handbook commonplace (which the item explicitly concedes), and the comparative fixity of the Byzantine proskynesis donor format is treated at length (Rico Franses, Donor Portraits in Byzantine Art, 2018). Not located: the item's paired dated-curve operationalization -- that on >= 100 Latin and >= 50 Byzantine dated donor images the Latin donor-to-holy-figure height ratio has a positive secular trend whose decadal median crosses 0.85 between 1380 and 1440, WHILE the Byzantine trend over 1100-1450 is statistically indistinguishable from zero (median within +/- 0.05 of its 12th-century value). The divergence's two directions are documented; the quantified crossing-point-vs-flat-line measurement is unrun.

• Rico Franses, Donor Portraits in Byzantine Art: The Vicissitudes of Contact between Human and Divine (Cambridge University Press, 2018) — Byzantine donor scale and the relatively fixed proskynesis format; the Byzantine arm of the divergence.
• Index of Medieval Art donor-image records with dates, measured on BL, BnF and e-codices digitizations — The kill dataset for the paired Latin/Byzantine donor-to-holy-figure height-ratio trends.

Predictions

No prediction registered yet.