20 JUL 2026

Day 201

The unexamined life is not worth living.

Socrates · Plato, Apology

A small gold locket set with diamonds and coloured vitreous enamel, made to hold a miniature painted on vellum.

I · THE OBJECT · BRITISH MUSEUM

The Lyte Jewel

British · 1610 · Gold, diamond, enamel, vellum

A gold and enamel locket of 1610, limned by Nicholas Hilliard on vellum, kept in the British Museum and still known by the name of a Jacobean antiquary.

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II · THE IDEA · ARTIFICIAL INTELLIGENCE

Memory-Efficient Backpropagation with Reversible Layers

training · reversible residual networks · 1707.04585

Invertible residual blocks let a network discard intermediate activations after the forward pass, then rebuild them on the way back — spending extra compute to free memory.

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In a dark interior an old man in a red cloak bends over a shabbily dressed youth who kneels barefoot against him. A standing man watches from the right; other figures fill the shadows behind.

III · THE WORK · ART HISTORY

The Return of the Prodigal Son

Rembrandt · c. 1665–1668 · Oil on canvas

A kneeling son, a father’s hands, and an older brother who will not join the embrace — Rembrandt’s large late painting of forgiveness held in silence.

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