The subject of history is the life of peoples and of humanity. To catch and pin down in words--that is, to describe directly the life, not only of humanity, but even of a single people, appears to be impossible.
By law of periodical repetition, everything which has happened once must happen again and again -- and not capriciously, but at regular periods, and each thing in its own period, not another's and each obeying its own law.
No one can read the history of astronomy without perceiving that Copernicus, Newton, Laplace, are not new men, or a new kind of men, but that Thales, Anaximenes, Hipparchus, Empodocles, Aristorchus, Pythagorus, Oenipodes, had anticipated them.