9 JAN 2026

Day 9

Man is only a reed, the weakest in nature, but he is a thinking reed.

Blaise Pascal · Pensées

A gold-covered goat standing upright on its hind legs, forelegs resting on a gold and shell flowering plant. The body is inlaid with lapis lazuli and shell, mounted on a modern wooden support.

I · THE OBJECT · BRITISH MUSEUM

Ram in a Thicket

Sumer · c. 2600–2400 BC · Ur, 1928

Leonard Woolley dug it out in pieces, stabilised the fragments with wax, and mounted them on a wooden core. Most of what you see in the case is original. Some of it is not.

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II · THE IDEA · ARTIFICIAL INTELLIGENCE

Activations: ReLU, GELU, SwiGLU

Foundations · ReLU 2010s, GELU 2016, SwiGLU 2020 · Feedforward blocks in transformers

A network of pure matrix multiplications can only learn straight lines. The activation function, applied between layers, is what permits a model to capture curves, boundaries and every other pattern worth learning.

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A tall Gothic cathedral with two unmatched spires, one plain and one ornate, and walls pierced by large rose windows and vertical lancets filled with coloured glass.

III · THE WORK · ART HISTORY

The Windows of Chartres Cathedral

Chartres, France · 1194–1220 · 113 metres (370 ft 9 in)

The glass at Chartres contains a cobalt compound whose exact recipe has been lost. The building around it was designed as a stone frame for coloured windows, not the other way round.

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