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The Daily Triptych004 / 365

4 JAN 2026

Day 4

I think, therefore I am.

René Descartes · Discourse on the Method
A crescent-shaped gold cape, heavily decorated with concentric bands of raised ribs and small circular bosses, fitted to cover the shoulders and upper chest with small armholes.

I · THE OBJECT · BRITISH MUSEUM

The Mold Cape

Bronze Age Britain · c. 1900–1600 BC · Gold

Hammered from a single sheet of gold and fitted so tightly it pinned the arms to the body, this Bronze Age cape was never meant for walking around in.

Enter lesson 6 MIN

II · THE IDEA · ARTIFICIAL INTELLIGENCE

Loss: How a Model Knows It Is Wrong

Foundations · Cross-entropy, negative log-likelihood · Single scalar per prediction

Training adjusts billions of weights, but every adjustment is steered by one scalar: a measure of surprise when the model's probability distribution meets the actual next token.

Enter lesson 7 MIN

Written before source checking was enforced · facts in this lesson are unverified

Painted cave interior with a vaulted ceiling covered in geometric and figural decoration. Celestial figures with flowing scarves float across the upper surfaces. The walls show rows of seated Buddhas and narrative scenes in ochre, blue, and red.

III · THE WORK · ART HISTORY

The Cave Paintings of Dunhuang

Dunhuang, Gansu province, China · 366 CE to 14th century · Cave temples

Buddhist pilgrims carved chambers into a desert cliff and painted them for a thousand years. Then someone walled up a room full of manuscripts and did not write down why.

Enter lesson 7 MIN

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