At the outset of Thucydides’s “archaeology” of the Peloponnesian War, the greatest “motion” of the city yet seen by either the Hellenes or barbarians or also possibly of all mankind, including the ancient Trojan War, Thucydides provides many opportunities for wonder. Pointing to later thinkers, like Hobbes, Thucydides gives an account of how the Hellenes came to be.

The early peoples of Hellas were not settled, uprooted like the Scythians of the Steppes as discussed in Herodotus. Tribes of fewer numbers were compelled by tribes of larger numbers -the rule of force reigned supreme in this “state of nature”. Men did not plant and grow food because settlements were frequently pirated, and men only cultivated the necessities of life devoid of capital or commerce. Therefore there was heavy competition among the tribes over fertile regions like Boetia or the Peloponnesus. These fertile regions caused certain individuals to seek enrichment, except in Attica where the soil was relatively poor and where many victims of war sought refuge until Attica could no longer maintain them all and they sought out colonies in Ionia.
According to Thucydides, the ancients were weak and barbarous, like the men of the Homeric epics. All of life was devoted to war, and like in Vico, we find the early cities established by the patriarch who provided shelter to the rootless many through both his virtue and wealth. The old Hellenes are like the modern barbarians in that life is governed by the superior rule of force. For example, in Thucydides’s opinion, Agamemnon’s ability to compel the Argives was less due to his oath of Tyndareus and more so to do with his superior strength (his vast navy). Fear was at least as strong as love in the Trojan expedition under Agamemnon, and Chaos and tyranny, rather than freedom, ruled the lives of the early Hellenic peoples. Slowly hereditary monarchies degenerated into tyrannies as wealth grew for the Hellenes and new technologies were developed, such as the triremes that might have originated from the Corcyrans.
“Again, wherever there were tyrants, their habit of providing simply for themselves, of looking solely to their own personal comfort and family aggrandizement, made safety the great aim of their policy, and prevented anything great proceeding from them; though they would each have their affairs with their immediate neighbors” (1.17).
It was Sparta that would eventually put down the tyrannies thanks to their long-lasting regime free from tyranny for over 400 years, supported by Athens (Note: this is distinct from the Athenian account of their victory without the help of Sparta who was busy at a religious festival when the Medes invaded). After the repulsion of the Medes (Persians), the Hellenes split into two factions: the Spartans, the chief military power of the Hellenes who established their regime by building loyal oligarchies at each polis under their protection, and the Athenians, the democracy and naval power who imposed monetary tributes on their subordinate city-states. However, Thucydides is critical of Athens, the first city to embrace a relaxed and luxurious style of life. Thucydides muses on the distinctions between Spartan and Athenian culture -while he maintains the superiority of the Spartans, he also imagines that years from now the ruins of Athens will be looked upon as greater than those of Sparta. He states that while many accept the account of the origins of the Peloponnesian War to be the breaking of the peace treaty between Athens and the Peloponnesians, Thucydides claims the chief cause must be the alarming growth of Athens that Sparta found threatening.
In a dispute between the Corcyrans and the Corinthians, both request aid from Athens, but Athens chooses Corcyra by providing defensive naval support. This threatens Sparta and her allies. Corinth attacks Sparta for allowing the Athenian tyranny to spread, and the Athenians try to self-righteously defend their actions.
It should be noted that Thucydides gives an account of the Hellenes -a city in “motion”, i.e. at war. Socrates calls for this in the Timaeus, the Platonic dialogue immediately following the Republic, and a similar account of Hellenic origins and decay is given in the Laws. In the same way that Plato uses the particular to explore the universal, i.e. the life and death of Socrates, so Thucydides uses the particular -the “great motion” of the war between Sparta and Athens, to explore the universal. However unlike the philosopher, Thucydides’s horizon extends only as far as the city, not in speech but in motion. That is, his history is an account the particular cities in situations that have already come to pass in an effort to proceed to a better account of the good and just city.
For this reading I used the impeccable Landmark edition by businessman turned classical scholar, Robert B. Strassler.