Polybius : biography
Polybius ( c. 200–c. 118 BC) was a Greek historian of the Hellenistic Period noted for his work, The Histories, which covered the period of 264–146 BC in detail. The work describes in part the rise of the Roman Republic and its gradual domination over Greece. Polybius is also renowned for his ideas concerning the separation of powers in government, later used in Montesquieu’s The Spirit of the Laws and in the drafting of the United States Constitution.
Polybius was born in Arcadia around 200 BC. He was the son of Lycortas, a Greek politician who became Cavalry Commander of the Achaean League. His father’s opposition to Roman control of Macedonia resulted in his imprisonment. Polybius was then deported to Rome, where Lucius Aemilius Paulus employed him to tutor his two sons.
Polybius had the opportunity to return to Macedonia in 152 BC; he elected to stay, however, in Rome, as by that time he had placed his allegiance in the Roman Republic. He became a close friend of the Roman military commander Scipio Aemilianus, accompanying the general to Hispania and Africa. Polybius’s The Histories provides a detailed account of Rome’s ascent to empire and included his eyewitness account of the Sack of Carthage in 146 BC. Polybius held that historians should only chronicle events whose participants the historian was able to interview, and was among the first to champion the notion of having factual integrity in historical writing, while avoiding bias.
Polybius was responsible for a useful tool in telegraphy that allowed letters to be easily signaled using a numerical system (mentioned in ). This idea also lends itself to cryptographic manipulation and steganography.
This was known as the "Polybius square", where the letters of the alphabet were arranged left to right, top to bottom in a 5 x 5 square, (when used with the modern 26 letter alphabet, the letters "I" and "J" are combined). Five numbers were then aligned on the outside top of the square, and five numbers on the left side of the square vertically. Usually these numbers were arranged 1 through 5. By cross-referencing the two numbers along the grid of the square, a letter could be deduced.
In the The Histories, he specifies how this cypher could be used in fire signals, where long-range messages could be sent by means of torches raised and lowered to signify the column and row of each letter. This was a great leap forward from previous fire signaling, which could send prearranged codes only (such as, ‘if we light the fire, it means that the enemy has arrived’).
Other writings of scientific interest include detailed discussions of the machines Archimedes created for the defense of Syracuse against the Romans, where he praises the ‘old man’ and his engineering in the highest terms, and an analysis of the usefulness of astronomy to generals (both in the Histories).
Polybius wrote several works, the majority of which are lost. His earliest work was a biography of the Greek statesman Philopoemen; this work was later used as a source by Plutarch when composing his Parallel Lives, however the original Polybian text is lost. In addition, Polybius wrote an extensive treatise entitled Tactics, which may have detailed Roman and Greek military tactics. Small parts of this work may survive in his major Histories, but the work itself is lost, as well. Another missing work was a historical monograph on the events of the Numantine War. The largest Polybian work was, of course, his Histories, of which only the first five books survive entirely intact, along with a large portion of the sixth book and fragments of the rest. Along with Cato the Elder (234–149 BC), he can be considered one of the founding fathers of Roman historiography.