Knowing Oneself

Natty, the know-it-all nautilus, was bobbing along, by the side of his favorite coral reef, when he saw another nautilus named Nellie.

Natty said, “Care to go for a ride? I could teach you a lot. For instance, do you know the meaning of the word nautilus?”

“No,” Nellie said. “I don’t.”

“I will tell you what it means,” Natty said. “It means a sailor, and nothing could be more appropriate. Nautiluses do not swim like fishes, but we sail the mighty seas, don’t we?"

"Yes," said Nellie. "We do."

"Did you know, for instance, we have hollow chambers? We use them the way submarines use ballast tanks. We fill our chambers with air or water depending on whether we want to rise or sink. You know the concept of buoyancy, don’t you?”

“No,” Nellie said, shaking her head. “Never heard of it.”

“I will tell you what that means,” Natty said. “If we fill our chambers with air, we float. If we fill our chambers with water, we sink. We can rise or sink as we want. We use the concept of jet propulsion too. You know jet propulsion, don't you?”

“No.” Nellie shook her head again. “Never heard of that either.”

“Good grief, how little you know. We fill our siphons with water and when we eject that water, like a jet, it creates a force in the opposite direction. That's why we move in the opposite direction of the jet. I will show you jet propulsion. Watch."

"No," Nellie said. "I won't."

"What?" Natty asked, aghast. "I'm going to TEACH you something! Why not?"

“Because we move backwards. We cannot see where we are going. There is an octopus right behind you and if you jet propel at this moment, you will head into that octopus's mouth."

"Oh," Natty said. "Ummm. Hmmm. Well. Yes. Thank you."