Living Worlds
A rooftop in Pataliputra at dusk where a young astronomer and students mark the rising stars, the Ganges below.

100–700 CE · Pataliputra, 499 CE

Place Value

A digit's place gives it its worth.

The law of Place Value

A digit's place gives it its worth.

Pataliputra, 499 CE: in a Gupta city on the Ganges, a 23-year-old named Aryabhata finishes a book of astronomy that counts with place value. The monastery at Nalanda is a few decades old.

A young astronomer marking star positions on a palm leaf by an oil lamp on a rooftop.

A life in Place Value · composite, based on the record

A student, twenty-three

He marks where each star rises and checks it against the book. Tomorrow night he will do it again.

Meanwhile, in the same age

Classical worlds

A Roman street about 100 CE: apartment blocks above shops, a fountain fed by an aqueduct, people of many origins in tunics, donkeys and porters.

The Greek and Roman World

Rome, about 100 CE

The plastered market plaza of Tikal with painted temple platforms, women selling maize drink and woven cloth.

The Plaza

Tikal, about 700 CE

A double-hulled voyaging canoe with pandanus sails on the open Pacific at dusk.

Which world will you live in?

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