The legacy of Mesopotamia: maths, time, memory

Detail

The mathematical tablets (c. 1800 BCE)

• What the tablets contain — school tablets from around 1800 BCE carry:
• multiplication and division tables
• tables of squares and square-roots
• tables of compound interest (money lent on interest, growing year by year)

• problems on volumes — how much earth in a field, how much water in a channel

• The famous √2 value — one tablet gives the square root of 2 as 1 + 24/60 + 51/60² + 10/60³.

• In our numbers this is 1.41421296.
• The true value is 1.41421356. So the Mesopotamian scribe was wrong only in the seventh decimal place.
• A tablet at Yale University shows a square with its diagonals: "30" written on one side, "1 24 51 10" written along the diagonal, and "42 25 35" under it — the same √2 value, used to get the diagonal of a square of side 30 [2].
• The scribe seems to have known a step-by-step method for finding square roots, not just a memorised answer [2].

The sexagesimal system — why 60 still rules our clocks

• Sexagesimal means counting in base 60 (we count in base 10). This is a Sumerian invention.
• It gave us three things we still use daily:
• the hour of 60 minutes
• the minute of 60 seconds

• the circle of 360 degrees

• Why 60? Because 60 divides cleanly by many numbers — 2, 3, 4, 5 and their multiples. That makes division easy, which matters when you have no decimal fractions [2].

• The Old Babylonians used place value (the position of a sign changes its worth) with base 60 [2].

Time reckoning — the calendar we inherited

• From Mesopotamia we get:
• the year of 12 months (lunar months, counted by the moon)
• the month of 4 weeks
• the day of 24 hours

• the hour of 60 minutes

• Astronomy was written down — eclipses and positions of stars were recorded by year, month and day. A dated record is what makes a pattern findable later.

• How it reached us — a long relay:
• Alexander's successors (the Greek kings who ruled West Asia after 323 BCE)
• → the Roman world
• → Islam (Arab scholars)
• → medieval Europe → us.

Why writing and schools made science possible

• No writing, no science. A story or song can live in people's mouths. A table of square roots cannot — it must be copied exactly.
• Schools did the copying — students copied older tablets again and again. This kept the knowledge fixed and correct.
• Some boys went further and trained as intellectuals — they built on the work of earlier scholars instead of starting fresh.
• Key exam point: moving narratives (epics, hymns) can stay oral; exact knowledge (maths, astronomy) needs written texts.

Pride in the city — the Gilgamesh Epic

• The Gilgamesh Epic is written on 12 tablets.
• Gilgamesh, ruler of Uruk, searches for immortality and fails.
• His comfort is not sons or fame in battle. He walks along the city wall of Uruk and admires its foundations of fired brick.
• The lesson NCERT draws: the city itself is the achievement — urban life was the thing Mesopotamians were proudest of.
• The epic survived mainly because copies sat in Assurbanipal's library at Nineveh [3].
• Other epics preserved the same way: Creation, Irra, Etana, Anzu [3].

An early library — Assurbanipal (668–627 BCE)

• Assurbanipal was the last great Assyrian king. He ruled from Nineveh.
• Even so, he accepted that Babylonia — not Assyria — was the centre of high culture. So he collected Babylonian learning.
• Size of the collection: about 1,000 texts spread over roughly 30,000 tablets, grouped by subject.
• Subjects: history, epics, omen literature (writings on signs that predict the future), astrology, hymns and poems.
• It was catalogued — clay basket-labels recorded the contents, e.g. "so many tablets about exorcism, written by X". This is a library catalogue, not a heap.
• How he got the texts — scribes were sent out by royal order to search temple libraries and copy every kind of text; these were added to tablets already held at Ashur, Calah (Nimrud) and Nineveh [3].
• Many tablets carry the royal ownership mark in their colophons (the note at the end of a tablet giving scribe, owner and date) [3].
• Where they are now: about 20,720 Assyrian tablets and fragments from this library are preserved in the British Museum [3].

Note: NCERT gives ~30,000 tablets collected by Assurbanipal; Britannica gives ~20,720 tablets and fragments surviving in the British Museum [3]. These are not in conflict — one counts what was gathered, the other what was excavated and kept.

• The language point: Sumerian stopped being spoken around 1800 BCE, but it was still taught in schools for over a thousand years.
• Result: a tablet written in 2000 BCE could still be read and understood in 650 BCE. That is a 1,350-year chain of literacy.

An early archaeologist — Nabonidus

• Nabonidus was the last ruler of independent Babylon (before the Persian conquest).
• Problem he faced: the office of High Priestess of Ur had been forgotten — nobody remembered how it worked.
• What he did: he used the stele of a king of c. 1150 BCE (a stone slab with carving and inscription) as evidence, read it, and reconstructed the office.
• He also found a broken statue of Sargon of Akkad and had craftsmen repair it.
• His own reason, in his words: "because of my reverence for the gods and respect for kingship".
• Why this matters: a king in the 6th century BCE was already digging up, reading and restoring objects 1,500 years older than himself. Mesopotamians studied their own past.

Prelims Hooks

• The sexagesimal (base-60) system — source of the 60-minute hour and 360° circle — is a Sumerian invention.
• Mesopotamian tablets give √2 as 1 + 24/60 + 51/60² + 10/60³ = 1.41421296; true value 1.41421356.
• The Yale tablet showing √2 writes "30" on the square's side and "1 24 51 10" along the diagonal [2].
• Base 60 was likely chosen because it has many divisors — 2, 3, 4, 5 — making division easy [2].
• The Gilgamesh Epic is written on 12 tablets; Gilgamesh finds comfort in the city wall of Uruk, built on fired-brick foundations.
• Assurbanipal ruled 668–627 BCE, was the last great Assyrian king, and ruled from Nineveh.
• His library held about 1,000 texts / 30,000 tablets, catalogued using clay basket-labels.
• About 20,720 Assyrian tablets and fragments from Nineveh are now in the British Museum [3].
• Sumerian ceased to be spoken c. 1800 BCE but was still taught; 2000 BCE tablets were readable in 650 BCE.
• Nabonidus, last independent ruler of Babylon, used a stele of c. 1150 BCE to restore the office of High Priestess of Ur, and repaired a statue of Sargon of Akkad.
• Mesopotamian time-units reached Europe via Alexander's successors → Rome → Islam → medieval Europe.

Mains Points

• Writing was the condition for science, not just a by-product of trade. Mesopotamia shows that exact knowledge — square-root tables, dated eclipse records, compound-interest problems — can only accumulate when it is written down and copied in schools. Oral cultures can carry epics; they cannot carry an error-free table. Useful whenever a GS-I answer compares literate and non-literate civilisations, including the contrast with the undeciphered Harappan script.
• Legacy is about transmission, not invention alone. The 60-minute hour survives today not because it was best, but because it passed through an unbroken chain — Sumer → Babylon → Alexander's successors → Rome → Islam → medieval Europe. Good example for questions on cultural diffusion and on Islam's role as a bridge between ancient and modern knowledge.
• The city as the highest value of Bronze Age Mesopotamia. Gilgamesh, denied immortality, settles for the wall of Uruk. Compare with Egypt, where the same urge for permanence went into royal tombs and pyramids, and with the Harappans, whose effort went into drains, baths and granaries with no royal monument. Same wish to outlive death, three different answers.
• Mesopotamians were the first to treat their own past as evidence. Assurbanipal built a catalogued library; Nabonidus read an old stele and restored a ruined statue. This is the earliest known pairing of archive-keeping and antiquarian restoration — a direct ancestor of modern archaeology and of bodies like the Archaeological Survey of India.