Achilles had overtaken the Tortoise, and had seated himself comfortably on its back

"So you've got to the end of our race-course?" said the Tortoise. "Even though it does consist of an infinite series of distances? I thought some wiseacre or other had proved that the thing couldn't be done?"

"It can be done,Achilles had overtaken the Tortoise, and had seated himself comfortably on its back." said Achilles.

"It has been done! Solvitur ambulando. You see the distances were constantly diminishing; and so --"But if they had been constantly increasing?" the Tortoise interrupted "How then?"

"Then I shouldn't be here," Achilles modestly replied; "and you would have got several times round the world, by this time!"
What the Tortoise Said to Achilles - Lewis Carrol.

Achilles and the Tortoise  (アキレスと亀 / Achilles to Kami), filme - Takeshi Kitano.