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The Daily Triptych006 / 365

6 JAN 2026

Day 6

Custom is the great guide of human life.

David Hume · An Enquiry Concerning Human Understanding
Two bronze wine jugs with swelling bodies, high curved handles, and trefoil spouts, their surfaces covered in geometric patterns, stylised animals, and red coral studs. A small bronze duck sits at the base of each handle.

I · THE OBJECT · BRITISH MUSEUM

The Basse-Yutz Flagons

Celtic, La Tène · 5th century BC · Copper, coral, vitreous enamel

Two wine jugs made in the fifth century BC, north of the Alps, carry Mediterranean coral and Etruscan shapes into Celtic hands — and a bronze duck swims toward the spout as wine pours.

Enter lesson 6 MIN

II · THE IDEA · ARTIFICIAL INTELLIGENCE

Backpropagation

Foundations · Machine learning · 1960s–1980s, independently rediscovered several times

A neural network has millions of weights, each contributing to the final output. Backpropagation computes how much to adjust every single one, in a single backwards pass through the graph.

Enter lesson 7 MIN

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

Reddish-brown rock paintings on a pale sandstone surface showing cattle with varied markings, human figures with rounded heads, and overlapping images of animals from different periods.

III · THE WORK · ART HISTORY

The Rock Art of Tassili n'Ajjer

Tassili n'Ajjer plateau, south-eastern Algeria · Neolithic and earlier · Pigment on sedimentary rock

Cattle graze, swimmers dive, hunters track game across sandstone walls in the central Sahara. The paintings record a climate that disappeared six thousand years ago.

Enter lesson 7 MIN

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