Is reading about historical events a blessing or a curse, or even an imbecility? Is it the royal road to political understanding, or a dark and damning diversion from true political principles? Plato invented the new genre of philosophical dialogue a little later than, and in distinction from, Thucydides’s invention of the new genre of contemporary historical reconstruction, yet for the inheritors of both, such as Plutarch, and those who read him, such as Rousseau, to reflect on the history of classical Athens and later Rome was an indispensable part of the emerging tradition of political theorising. It is only in light of certain developments, themselves historical, that the significance of history for normative political theory can even be put into question. Those developments have led to a state in which – to caricature, for the sake of emphasis – some theorists read Machiavelli and Hobbes, without feeling it essential to read their own sources such as Thucydides, Livy, Sallust, and Plutarch, while others dispense with all these prior writers in practising a pure theoretical construction or analysis.