The use of numbers seems to us so obvious that we tend to consider it an innate attitude of man, such as walking or speaking; in reality it has not always been counted as we currently do, nor written the figures in the same way. The history of calculation is the story of a great invention distributed over many millennia, a complex evolution that bases the great civilizations of the past. A few centuries ago in Europe it was calculated not already using figures, but on the fingers of the hand, when not with tokens on boards, and the accounting was kept with carved sticks.

Where and when did this fantastic adventure of human intelligence begin? The event is lost in the night of the prehistoric ages, but one thing is certain: there was a time when man knew absolutely not to count. The proof is given by the fact that today there are several “primitive” populations incapable of conceiving the concept of number and that they ignore even that two plus two makes four. Everything must have started with that factory that is called “ownership of mating” that allows to easily compare two collections without resorting to the abstract compute. It was certainly thanks to this principle that the prehistoric man, over several millennia, could make arithmetic even before becoming aware and knowing what an abstract number is. I then had access to the abstraction of numbers, learned the difference between the cardinal number and the ordinal number, the man soon found himself struggling with a problem: how to indicate high numbers with the least possible amount of symbols? The basic idea was the grouping by tens, from the mathematicians this is called “use the base ten”. However, not all cultures have solved the problem of the basis in the same way, and the ten was not the only one to whom men referred over time.

The main events that have completely modified the existence of man have been the use of fire, the development of agriculture and its urban and technological progress, the invention of writing and that of zero and the figures called “Arab”. Like writing, zero and our modern figures are among the most powerful intellectual instruments available to today’s man, and unrealizable calculations for millennia were made possible thanks to their discovery. This story began a little more than five thousand years ago when certain societies elaborated the idea of representing numbers by graphic signs, the figures were thus invented.

The exhibition For a history of calculation, presented at the Liceo Righi di Cesena, is of course only a small synthesis, a taste, of the section Calculation of the Museum of Pennabilli. In the exhibition, through the mathematical instruments exposed in the windows, the interactive table and the explanatory posters trace the long history of the invention of numbers: from the prehistory of numbers to how man has learned to count, the invention of the base and the figures, the importance of the great civilizations of the past, the revolutionary principle of zero, the birth of the Arabic figures, the tools that have helped man to pass from “fake” to “fake” to pass from the ethics.

EXHIBLE

  • display case 1: The prehistory of the calculation: carvings on bone or wood, stones, knots on ropes (35000-20000 BCE), tablets and calculus Sumerians (3100 BCE), Sieve of Eratosthenes (250 BCE) for the search of the first numbers, Roman abacus (sec I CE), fragment of Roman stone.
  • display houses 2: enclosed machines: suan pan (pallottoliere or abacus) chinese, counting board (1000 AD), quipu inca (sec XII), stone of the Sun or Aztec calendar (sec XV), Napier’s bones (1617), carved rulers of Swiss shepherds (late 18th century).
  • display case 3: The dawn of science (sec XVII and XVIII): The logarithms (Nepero-1614; Briggs-1617), circular slide rule, modern rulers, octating and sender (mathematics, astronomy, navigation), books of mathematics.
  • display case 4: Mechanical calculators (sec XIX and XX): Comptometer, Burrough calculator, Triumphator, Thates, Torpedo, Addiator.