27 AUG 2026

Day 239

We suffer more often in imagination than in reality.

Seneca · Letters to Lucilius

Three hinged panels of pale carved ivory forming a small triptych, the side leaves set to close over the centre, shown as a compact portable object.

I · THE OBJECT · BRITISH MUSEUM

John Grandisson Triptych

Medieval England · c. 1330 · Ivory

An English ivory triptych of about 1330, now in the British Museum under the inventory number 1861,0416.1. Three hinged leaves, one material, and a name that outlasted its maker.

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II · THE IDEA · ARTIFICIAL INTELLIGENCE

Ablation: Reading Function by Removing Parts

interpretability · component ablation · BERT interpretability illusion

Zero a neuron, drop an attention head, and watch what breaks. The method is simple; the conclusions it supports are often thinner than they look.

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A half-length young man in a dark cap and garment against a plain dark ground, facing slightly aside; a hand in the lower part of the panel holds a folded sheet of music. The face is finely modelled; the torso is flatter and less finished.

III · THE WORK · ART HISTORY

Portrait of a Musician

Leonardo da Vinci · 1485 · Oil on panel

A small unfinished panel in Milan holds a young man with a sheaf of music. The face is almost certainly Leonardo's; the rest of the picture is less certain, and the name is lost.

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