https://doi.org/10.1515/9783110583557-011 Christopher Pelling Causes in competition: Herodotus and Hippocratics � Herodotus has a lot of explaining to do. The proem’s promise of content is im- mensely broad, for the phrase τὰ γενόμενα ἐξ ἀνθρώπων, ‘things that originate from humans’, embraces not just the history of events but their ἔργα in a broader sense: what they have built, how they behave, what they believe, the stories they tell. 1 But even that rubric proves inadequate to the content that follows, as pro- grammatic statements so often do: they are first bids, ones that can be renuanced as the work goes on. 2 In Herodotus’ case the revision makes his canvas even broader, as he will include various phenomena which belong to the world of na- ture rather than human ‘doings’: why the Nile floods, why Thessaly has the phys- ical shape it does, why Scythian oxen have no horns, why the most lethal animals are the least fertile (2.20–7, 7.129–30, 4.28–9, 3.108–9). Conceivably these phe- nomena might be, or link with, the doings of gods, though Herodotus himself shows only intermittent commitment to seeing them that way; 3 but they are cer- tainly not γενόμενα ἐξ ἀνθρώπων. Still, they are μεγάλα τε καὶ θωμαστά, in that second key phrase of the proem, even if no longer ‘achieved partly by Greeks and partly by barbarians’, and so the extension is still in much of the same spirit. What makes them θωμαστά, too, is not merely that these things happen and hap- pened but also why. 4 The proem signals that as well: the particular example on which the proem ends makes that clear – ‘other things and the αἰτίη why they fought one another’. That too still focuses on human doings, understandably given the human focus of the sentence so far; but if the scope is to extend into nature as well, it would be odd if the quest for explanation did not extend too, and that is certainly what the text goes on to do. Still, explaining things is tricky; to talk of a single αἰτίη, just one, may be trickier still; and it is still debated by philosophers and historiographic theorists �� 1 Immerwahr 1960; Drexler 1972, 28–39. 2 Gribble 1998, 57 makes a similar point about Thucydides’ programmatic statement at 1.23.6. 3 Cf. esp. Romm 2006, 182–6. 4 Cf. Fowler 2006, 31–2; Bakker 2002, 13–14, 17–18.