The Nile’s Flooding and the Limits of Logic May 6, 2015Author: Beach Combing | in : Ancient , trackback
Herodotus was fascinated by Egypt, a kind of topsy-turvy version of his Greek world, and above all, in the second book of the Histories, he shows that he was fascinated by the Nile that ran through Egypt. The great mystery with the Nile for Herodotus and his readers, though it seems to have little bothered Egyptians, was why the Nile flooded seasonally. That this mighty river rose in the summer was a matter of record, but what natural mechanism led to the clockwork soaking of the Egyptian Delta? These are the explanations that Herodotus had come across:
1) Winds blowing north hold back the Nile and when these winds recede, in the summer, the Nile shoots forward and floods.
2) The Nile comes from the world ocean (though it is not clear to Beach why this should lead to flooding)
3) The Nile floods because of melting snows
Herodotus elegantly dismisses these three explanations and adds his own, which he believes is correct.
4) The sun is ‘blown’ in winter nearer to the head of the Nile and there burns up water, the Nile returning to normal flood when the sun moves off in summer.
What is wonderful about these points and Herodotus’ elaboration is that the Greek’s logic is flawless. Anyone who has read Herodotus will know that despite the confusion on his great canvas he gives constant evidence of someone with a limpid mind. Here he is, for example, dismissing the melting snow argument:
Now, as the Nile flows out of Libya, through Ethiopia, into Egypt, how is it possible that it can be formed of melted snow, running, as it does, from the hottest regions of the world into cooler countries? Many are the proofs whereby any one capable of reasoning on the subject may be convinced that it is most unlikely this should be the case. The first and strongest argument is furnished by the winds, which always blow hot from these regions. The second is that rain and frost are unknown there. Now whenever snow falls, it must of necessity rain within five days; so that, if there were snow, there must be rain also in those parts. Thirdly, it is certain that the natives of the country are black with the heat, that the kites and the swallows remain there the whole year, and that the cranes, when they fly from the rigours of a Scythian winter, flock thither to pass the cold season. If then, in the country whence the Nile has its source, or in that through which it flows, there fell ever so little snow, it is absolutely impossible that any of these circumstances could take place.
But Herodotus who argues with such authority was absolutely wrong about a sun being blown around the heavens, as were the three rival theories from the Greek world. For Beach it is a healthy reminder that your logic can be sharp as a diamond knife, but if you don’t have the data you will never get the correct answer. Or won’t you? The Egyptians who had less pretensions to predicate logic seems to have stumbled upon the truth or a poetic reflex of the same. The flooding of the Nile was known by them as the Tears of Isis: and of course the genuine explanation for that flooding is the massive rainstorms to the south in the mountains of Sudan, the inundations from which passed down to the Delta and watered one of the most exciting civilizations of the ancient world.
And just in case anyone wants to defend the ‘logic revolution’ by pointing out that a true logician would recognise the lack of data: Beach would concede the point, but would ask how many logicians seriously have the good sense to acknowledge the limits of their data? Wisdom and intelligence: very different things.
Other ancient or medieval examples of flawless logic and flawed conclusions: drbeachcombing AT yahoo DOT com