VI
1
2
Water is the first cause alleged: more authors than one adopt this view, but it is not stated by all in the same terms. Thales of Miletus is convinced that the whole earth floats, and is upborne by moisture lying beneath it, which you may call either Ocean or the great sea, or still mere elemental water of a different character from the sea, the simple ingredient, moisture. In these waves, in his opinion, the globe is supported like some huge lumbering vessel in the water which bears it. It is unnecessary for me to reproduce his reasons for supposing that the heaviest part of the world cannot be sustained in such a rare and nimble element as air: for the earth’s position is not the question here but its movement. By way of argument, to prove that water is the cause, he adduces the fact that in every considerable earthquake, as a rule, new springs burst out. So if a boat leans over to one side away from the straight, the result is that it ships water. And, generally speaking, in the case of all objects which water supports, if they are unduly sunk, the water either pours over them or at any rate rises to right and left above its ordinary height.
3
Now, no lengthened consideration is needed to prove the falsity of this view. Why, if the earth were supported by water, and from time to time shaken by it, it would be in perpetual shock; the wonder would be not that it was tossed about sometimes, but that it was ever at rest. Then, again, it would be shaken all over and not at a single point: we never find only half the ship tossed by the waves. But, according to present experience, a shock never occurs over the whole earth simultaneously, but is always felt at some particular spot. How, then, can it be that what is carried as a whole is not shaken as a whole, if the shock comes from the body by which it is carried?
4
But, it may be urged, why do waters burst out at the time of earthquakes? Well, in the first place, there has often been earthquake without any fresh supply of water appearing. Secondly, if the supposed cause of the water rushing forth were the true one, it would pour all round the sides of the earth, as we see happening under similar circumstances in sea and rivers: when boats sink, the increase of water shows itself chiefly over the sides. Finally, the outburst of waters which Thales describes would not be so small as he says, nor would it ooze in like bilge-water through a chink, but from the exhaustless reservoir that upbears all creation, a mighty deluge would ensue.