Science in the ancient world

Science in the ancient world includes the earliest times when people started to explore and understand the world around them. Before writing was invented, people shared knowledge through stories and spoken words. Once writing began, it helped people keep and share their knowledge more accurately.

The first scientific ideas came from the Ancient Near East, especially in Ancient Egypt and Mesopotamia (in today’s Iraq). Later, science developed in Persia, Greece, Rome, India, China, and Mesoamerica. Even though ideas like alchemy and astrology became less important later on, these ancient cultures helped create the beginnings of modern science.

Ancient Near East – Mesopotamia

Around 3500 BC, in Sumer (a region in Mesopotamia), people began writing down what they saw in the sky. They used numbers and symbols to record their observations.

Mathematics

People in Mesopotamia were already using math very early. A famous clay tablet called Plimpton 322 (from around 1800 BC) shows they understood the Pythagorean theorem (a math rule about triangles). The tablet lists number groups like (3, 4, 5) and (5, 12, 13), which fit that rule.

Astronomy

The Babylonians were some of the first people to study the stars and planets using math. They wrote down their findings on clay tablets. They knew about the movement of the stars, the Sun, the Moon, and the planets. They also created calendars based on the solar year and the lunar month.

They could predict things like:

• The phases of the Moon
• How long days would be during the year
• Solar and lunar eclipses

A few ancient scientists are known by name. One was Kidinnu, who figured out a very accurate length for the solar year—his number is still used in calendars today.

Later scientists like Hipparchus and Al-Battani used this data to learn even more. Al-Battani calculated how Earth’s axis slowly moves (called precession). His number was very close to the one we use today.

At that time, astronomy and astrology (the study of horoscopes and omens) were closely linked. Over time, Babylonian astronomy focused more on astrology.

Archaeology in Ancient Mesopotamia

After the fall of many ancient kingdoms (around 1200 BC), science still continued in some places. One king, Nabonidus of the Neo-Babylonian Empire, acted like the first archaeologist.

Around 550 BC, he found old items from temples that were built by an earlier king, Naram-Sin (from around 2200 BC). Nabonidus studied these objects and tried to figure out how old they were. He was the first known person in history to try dating ancient artifacts, even though his guesses were not always correct.

Ancient Egypt

Ancient Egypt made many important discoveries in astronomy, mathematics, and medicine. It was also a major center for alchemy, a practice that mixed early science and magic and later influenced Western science.

Architecture, engineering, and math

The Egyptians used geometry to measure land, especially after the Nile River flooded each year and washed away farm borders. They used simple math rules, like the 3–4–5 triangle, to build straight and solid structures. These rules helped them design buildings such as temples and pyramids, often using posts and lintels (horizontal beams supported by vertical ones).

Writing

Egyptians used hieroglyphs, a system of picture writing. This writing later helped create the Proto-Sinaitic script, which became the ancestor of alphabets like Phoenician. Many modern alphabets—such as Hebrew, Greek, Latin, Arabic, and Cyrillic—developed from this.

The city of Alexandria in Egypt was famous for its great library, which collected books and knowledge from many cultures. When Alexandria came under Roman rule, the library was damaged by fire and was finally destroyed by 642 AD. Much ancient knowledge was lost with it.

Medicine

Egyptian doctors were some of the first to study and treat health problems. One of the oldest medical texts, the Edwin Smith Papyrus, even describes the brain, making it one of the earliest works related to neuroscience. Ancient Egyptian medicine included steps like:

• Examining the patient
• Diagnosing the problem
• Giving treatment
• Predicting the outcome

This approach was similar to the scientific method used in modern medicine.

Another text, the Ebers Papyrus (from around 1550 BC), shows that Egyptians used experience and observation (called empiricism) in their treatments.

However, not all their medical methods were useful. A study by Michael D. Parkins found that 72% of treatments in the Hearst Papyrus likely had no healing power. Some methods—like using cow dung, lizard blood, or fly specks—could have been harmful.

Egyptian medicine also involved things like:

• Piercing ears
• Tattooing
• Treating wounds (often in unsafe ways)

These practices sometimes led to infections like tetanus. Even though not all treatments were effective, ancient Egypt laid the groundwork for the idea of studying and treating diseases scientifically.

Persia

In ancient Persia, especially during the time of the Sassanid Empire, people focused a lot on math and astronomy (the study of stars and planets). A famous learning center from this time was the Academy of Gondishapur, where many scholars worked.

During this time, astronomical tables (charts of star and planet movements) were created. These ideas and methods were later used by Muslim scientists during the Islamic Golden Age.

In the middle of the Sasanian period, Greek knowledge came to Persia, especially through Christian ideas and the Syriac language (a form of Aramaic). This helped mix Greek and Persian science.

Later, in the Early Middle Ages, Persia became an important center for Islamic science. After the Umayyad and Abbasid empires were created, many Persian scholars moved to the capitals of these Islamic kingdoms to share their knowledge and continue learning.

Greco-Roman World

The Greco-Roman world (also called classical antiquity) made many important discoveries in areas like anatomy, animals, plants, minerals, geography, math, and astronomy. Scholars also began to ask deeper questions about how and why things change in nature.

Scientific thinking

During the Hellenistic period (after Alexander the Great), Greek thinkers used math and careful observation to study the world. They didn’t just guess—they tested their ideas.

Science had two goals:

• To solve real-life problems, like making calendars or improving medicine
• To answer big questions about nature (this was called natural philosophy)

The first scientists were often called natural philosophers. They thought of themselves as smart workers or followers of certain beliefs.

Early Greek thinkers

Thales (6th century BC) is known as the "father of science". He tried to explain things like lightning and earthquakes without saying they were caused by gods.

Pythagoras started a school that studied math and was the first to say the Earth is round.

Around 385 BC, Plato started the Academy, a school for deep thinking. His student Aristotle helped start a “scientific revolution,” which grew in the 3rd and 2nd centuries BC with great minds like:

• Eratosthenes
• Euclid
• Aristarchus of Samos
• Hipparchus
• Archimedes

Plato and Aristotle also helped create logical thinking (like using evidence to prove something), which is still used in science today.

Astronomy and engineering

A famous invention from this time is the Antikythera mechanism, an ancient machine that could track planets and stars.

Aristarchus of Samos said the Sun is at the center of the Solar System (heliocentric model).

Eratosthenes figured out the size of the Earth with amazing accuracy.

Hipparchus made the first organized map of the stars.

Mathematics

Euclid wrote The Elements, a book that shaped modern math rules, including ideas like axioms and proofs.

Archimedes worked on geometry, calculated pi, and made discoveries in physics, like how levers and water pressure work.

Medicine

Herophilos was one of the first to dissect human bodies to learn how they work. He studied the nervous system.

Hippocrates and his followers carefully described diseases and how to treat them.

Galen did brain and eye surgeries, some of which were not repeated for over 1,000 years.

Minerals and nature

Theophrastus wrote about plants, animals, and minerals. He was one of the first to classify them by their features, like hardness.

Pliny the Elder wrote a huge book called Natural History in 77 AD. He described the shape of diamonds, noticed how crystals grow, and explained that amber comes from tree sap because he found insects trapped inside it.

Pliny’s work helped start the science of mineralogy and crystallography (the study of crystals).

Indian Subcontinent

Ancient India made important progress in science and technology. One example is the Iron Pillar of Delhi, which shows that India was skilled in working with metals a long time ago.

Math and engineering

In the Indus Valley Civilization (Harappa and Mohenjo-daro), people used practical math:

• They made bricks in the ratio 4:2:1, which made buildings stronger.
• They used a standard system of weights, often shaped like cubes, cones, and cylinders. This shows they understood geometry.
• They made rulers to measure things very accurately. A ruler found in Mohenjo-daro had units as small as 3.4 cm, divided into 10 parts.

Later, between 400–1200 AD, Indian mathematicians like Aryabhata, Brahmagupta, Bhaskara II, and Mahaviracharya made big discoveries:

• They helped develop the decimal system, zero, negative numbers, and algebra.
• They improved trigonometry, creating the modern ideas of sine and cosine.
• The Hindu-Arabic number system, which we use today, came from India. A French monk (later Pope Sylvester II) helped spread it in Europe in the 11th century.

The Bakhshali manuscript (dated between 200–600 AD) shows the use of negative numbers, later clearly explained by Brahmagupta.

Medicine

At Mehrgarh (a very old site), scientists found proof of tooth drilling in human skeletons from around 7000–5500 BC.

Ayurveda is India’s traditional medicine. It comes from the Atharvaveda, one of the holy books of Hinduism. Important texts include the Sushruta Samhita, written by Sushruta, who lived around 1000 BC. This book talks about surgery and treatments.

Ayurveda was used a lot during the time of Buddha (around 520 BC). During Chandragupta II’s rule (375–415 AD), Ayurveda was a main medical system in India. It continued to be widely used until colonial times.

Astronomy

Indian astronomy began with the Vedas. Early ideas included:

• The universe started from nothing.
• The Earth is round and supports itself.
• A year has 360 days, divided into 12 months of 30 days.

Later, during the Maurya to Vijayanagara Empires, Indian astronomy became more advanced:

• Aryabhata wrote books like the Aryabhatiya with important ideas about space and math.
• Varahamihira wrote the Pancha-siddhantika, which described five earlier systems of astronomy.

Indian astronomy used star-based (sidereal) calculations but sometimes also used season-based (tropical) systems.

Alchemy

Alchemy (early chemistry) was also popular. The philosopher Kanada said that all matter is made from small, indivisible parts called anu—like atoms in modern science.

Language and grammar

Indian scholars were the first to deeply study language:

• Panini wrote a very detailed grammar of Sanskrit, explaining how sounds and words work.
• Hemachandra wrote about Sanskrit and Prakrit languages. His book described six Prakrits and even the rare Apabhramsha language.

Their work helped shape the study of linguistics, the science of language.

Pre-Columbian Mesoamerica

This region includes ancient cultures like the Olmec, Zapotec, and Maya, who lived in parts of what are now Mexico and Central America before Columbus came to the Americas.

Writing

Between 900 BC and 300 BC, the Zapotec or Olmec people created the first full writing systems in the Americas. The Cascajal Block may be the oldest written record found.

The Maya developed their own writing system between 400 and 200 BC. It was based on earlier systems from the Olmecs and Zapotecs.

By 100 BC, the Maya script was used widely. It became the most advanced writing system in Mesoamerica, with symbols used for recording history, religion, astronomy, and math.

Mathematics

The Maya used a base-20 number system.

They also used the number zero, which was very advanced for the time.

They created special symbols for the numbers 1 to 19, which helped them build accurate calendars.

Astronomy

The Zapotecs made the first known calendar in Mesoamerica. It may have been influenced by the Olmecs.

The Maya took astronomy even further. Their writing includes calendar dates using symbols for numbers and time periods.

These dates helped track religious, political, and social events over years and even decades.