🧮History of Mathematics Unit 1 – Ancient Number Systems & Arithmetic

Ancient Number Systems Overview

• Ancient number systems developed independently in various civilizations across the world
• Early number systems were often based on tally marks, body parts (fingers, toes), or physical objects (pebbles, shells)
• As civilizations grew and trade expanded, more sophisticated number systems emerged to facilitate commerce and record-keeping
• Major ancient number systems include Egyptian, Babylonian, Greek, Roman, and Mayan
• Each system had its own unique symbols, rules for representation, and methods for performing arithmetic
• Understanding the evolution of number systems provides insight into the development of mathematical thought and its impact on society
• Ancient number systems laid the foundation for modern decimal system and mathematical notation

Early Counting Methods

• Tally marks one of the earliest forms of counting, used to keep track of quantities by making marks on bones, sticks, or cave walls
• Body parts like fingers and toes used for counting small quantities, leading to base-5, base-10, and base-20 systems
  • Base-5 systems common in cultures where counting was done on one hand
  • Base-10 systems developed from counting on both hands
  • Base-20 systems arose from counting all fingers and toes
• Physical objects such as pebbles, shells, or beads used as counters, with each object representing a single unit
• Knots tied in strings (quipu) used by Inca civilization to record numerical data and convey messages
• Development of abstract number words and symbols marked a significant advancement in human cognition and communication
• Early counting methods were limited in their ability to represent large numbers and perform complex calculations

Egyptian Numerals and Arithmetic

• Egyptian numerals one of the oldest known number systems, dating back to around 3000 BCE
• Hieroglyphic symbols used to represent powers of 10, with each symbol repeated as needed to represent a given number
  • Vertical stroke (|) represented 1
  • Heel bone (𓎆) represented 10
  • Coil of rope (𓍢) represented 100
  • Lotus flower (𓎘) represented 1,000
  • Bent finger (𓎛) represented 10,000
  • Tadpole (𓆓) represented 100,000
  • God figure (𓁨) represented 1,000,000
• Numbers written from largest to smallest value, with symbols grouped together and repeated as necessary
• Addition and subtraction performed by grouping and regrouping symbols, similar to modern decimal system
• Multiplication and division achieved through repeated addition and subtraction, or by using tables and factors
• Egyptian numerals were well-suited for record-keeping and everyday calculations, but lacked a symbol for zero and had limited fractional representation

Babylonian Mathematics

• Babylonian mathematics developed in ancient Mesopotamia (modern-day Iraq) around 2000 BCE
• Sexagesimal (base-60) number system used, with symbols representing 1 and 10, and positional notation to indicate place value
  • Vertical wedge (𒌋) represented 1
  • Chevron (𒌋𒌋) represented 10
  • Combinations of wedges and chevrons used to represent numbers up to 59
  • Positional notation allowed for representation of large numbers and fractions
• Babylonians had advanced understanding of arithmetic, algebra, and geometry
  • Developed quadratic equations and Pythagorean theorem
  • Used tables for multiplication, division, squares, cubes, and reciprocals
  • Calculated square roots and cubic roots
• Babylonian mathematics influenced Greek and Islamic mathematics, and their sexagesimal system is still used for measuring time and angles
• Lack of a true zero and reliance on context for interpreting positional notation were limitations of Babylonian system

Greek Number Systems

• Greeks used several number systems, including Attic, Ionic, and alphabetic numerals
• Attic numerals (5th century BCE) used tally marks and symbols for powers of 10
  • | (iota) represented 1
  • Π (pi) represented 5
  • Δ (delta) represented 10
  • H (eta) represented 100
  • X (chi) represented 1,000
  • M (mu) represented 10,000
• Ionic numerals (4th century BCE) used 27 letters of the Greek alphabet, with three obsolete letters (digamma, koppa, sampi) to represent numbers
  • α (alpha) to θ (theta) represented 1 to 9
  • ι (iota) to ϙ (koppa) represented 10 to 90
  • ρ (rho) to ϡ (sampi) represented 100 to 900
• Alphabetic numerals later replaced Ionic system, with 24 letters of the Greek alphabet representing numbers 1 to 9, 10 to 90, and 100 to 900
• Greeks developed mathematical concepts such as geometry, number theory, and mathematical proof
  • Euclid's Elements laid the foundation for modern geometry
  • Pythagoras and his followers studied properties of numbers and ratios
  • Archimedes made advances in geometry, mechanics, and hydrostatics
• Greek mathematics heavily influenced Western mathematics and philosophy, but their number systems were cumbersome for arithmetic calculations

Roman Numerals

• Roman numerals developed in ancient Rome, used throughout Roman Empire and medieval Europe
• Seven letters used to represent numbers: I (1), V (5), X (10), L (50), C (100), D (500), and M (1,000)
• Numbers formed by combining symbols, with smaller values placed before larger values for subtraction
  • IV represents 4 (5 - 1)
  • IX represents 9 (10 - 1)
  • XL represents 40 (50 - 10)
  • XC represents 90 (100 - 10)
• Larger numbers represented by placing a bar over a symbol, multiplying its value by 1,000
• Addition performed by combining symbols, subtraction by placing smaller value before larger value
• Multiplication and division were difficult and often performed using abacus or counting board
• Roman numerals well-suited for record-keeping and inscriptions, but cumbersome for arithmetic calculations
• Lack of a symbol for zero and limited positional notation were major limitations of Roman system
• Roman numerals gradually replaced by Hindu-Arabic numerals in medieval Europe, though still used for certain applications (clock faces, outlines, movie credits)

Mayan Number System

• Mayan civilization developed sophisticated number system and calendar in Central America, reaching its peak between 250 and 900 CE
• Vigesimal (base-20) number system used, with symbols for zero, one, and five
  • Shell or oval (0) represented zero
  • Dot (•) represented one
  • Bar (-) represented five
• Positional notation used, with each position representing a power of 20
  • Second position represented 20¹ (20)
  • Third position represented 20² (400)
  • Fourth position represented 20³ (8,000)
• Numbers written vertically, with the lowest position at the bottom and the highest at the top
• Addition and subtraction performed by combining symbols, with regrouping when necessary
• Multiplication and division likely performed using tables and repeated addition/subtraction
• Mayan numerals well-suited for astronomical calculations and calendar-keeping
  • Long Count calendar used for tracking historical events
  • Haab' calendar used for agricultural and religious purposes
  • Tzolk'in calendar used for divination and ceremonial purposes
• Mayan mathematics and astronomy were highly advanced for their time, but declined along with Mayan civilization

Practical Applications and Legacy

• Ancient number systems developed in response to practical needs, such as record-keeping, trade, taxation, and calendar-keeping
• Egyptian numerals used for accounting, inventory management, and construction projects
  • Rhind Mathematical Papyrus (1650 BCE) contains examples of mathematical problems and solutions
  • Egyptian fractions used to represent parts of a whole, important for distribution of goods and resources
• Babylonian mathematics applied to astronomy, agriculture, and engineering
  • Babylonians used mathematics to predict astronomical events, such as eclipses and planetary motions
  • Sexagesimal system used for measuring time and angles, still used today
• Greek mathematics laid the foundation for Western mathematics and science
  • Euclidean geometry used in architecture, art, and navigation
  • Greek philosophers used mathematics to explore abstract concepts and develop logical reasoning
• Roman numerals used for record-keeping, trade, and military organization
  • Roman numerals used to number chapters, pages, and sections in books and documents
  • Roman mile (mille passus) used to measure distances in Roman Empire
• Mayan mathematics and astronomy used for calendar-keeping, agriculture, and religious ceremonies
  • Mayan Long Count calendar used to record historical events and predict future ones
  • Mayan astronomy used to track the movements of celestial bodies and plan agricultural activities
• Ancient number systems and mathematical concepts continue to influence modern mathematics and science
  • Hindu-Arabic numerals and decimal system developed from earlier number systems
  • Algebra and geometry have their roots in ancient Babylonian and Greek mathematics
  • Study of ancient number systems and mathematics provides insight into the development of human thought and civilization