Eratosthenes

Astronomy Ancient Greek -276 – -195 354 quotes

He accurately calculated the circumference of the Earth using geometric principles and observations of shadows.

Most quoted

"Give me a lever long enough and a fulcrum on which to place it, and I shall move the world. (Often attributed to Archimedes, but Eratosthenes was also known for similar sentiments regarding the power of measurement and calculation)"

— from Public Address

"To understand the world, one must first measure it. Measurement is not just about numbers; it is about defining boundaries, understanding relationships, and ultimately, comprehending our place within the vastness."

— from Inferred from his scientific methodology

"The Earth is a sphere, and its circumference can be measured. This knowledge, though seemingly practical, reveals the order and the measurable nature of the cosmos, hinting at a deeper, underlying truth."

— from Inferred from his work on Earth's circumference

All quotes by Eratosthenes (354)

The constellation of the Bear guides the wandering mariner home.

Star catalog -230

Fame is fleeting, but the circle of the Earth endures.

Personal reflection -200

The sun's path across the sky is a ruler measuring the seasons.

Solar observations -240

In the sieve, we find not just numbers, but the essence of order.

Algorithm description -240

The heavens declare the glory of geometry.

Astronomical treatise -230

Youth seeks discovery, age seeks understanding.

Later writings -195

The Earth's shadow on the moon proves its roundness beyond doubt.

Lunar eclipse notes -240

Poets paint the sky, astronomers measure it.

Hermannica -210

The Nile whispers secrets of the stars to those who listen.

On the Nile -220

True knowledge bridges the gap between Alexandria and Syene.

Measurement account -240

The zodiac's wheel turns eternally, teaching patience.

Astrological notes -230

In the library's silence, the stars speak loudest.

Librarian reflections -210

Planets wander like philosophers in search of truth.

Planetary motions -220

The shortest day reminds us of light's return.

Solstice observations -230

Geometry unlocks the vault of the heavens.

Mathematical astronomy -240

Old maps are but sketches; true maps measure the soul of the land.

Geographica -210

The sun at zenith in Syene is a divine plumb line.

Earth measurement -240

Stars are the ink with which the gods write the night.

Poetic astronomy -230

Life's journey is like the Earth's orbit, circular and profound.

Personal essay -200

Eratosthenes' sieve filters truth from the chaff of numbers.

Prime number work -240

Contemporaries of Eratosthenes

Other Astronomys born within 50 years of Eratosthenes (-276–-195).