Heh, funny. But actually, no. All jellyfish really are is a bunch of organs and a membrane. A single-celled organism, like an ameboa (sp) doesn’t have a brain, and can’t think, but it can eat. It uses instinct.
Basically, the whole jellyfish is like a low-level brain, granting instinct but nothing else. So it knows instinctively how to eat.
It goes far beyond that. First of all, no, not everything thinks. To move, an animal needs to have a brain. Nothing more. It does not need to think to acheive movement. “Instinct” is what we call hardwired behavioural routines embedded in the brain. This is what allows a creature like a jellyfish to move and eat in the absecence of thought.
i have a dog called Pepper, a cat called Misha (polish name) and a bowl full of tropical fish (too many to remember them all) but i have another small bowl with my favourite fish that are called Orange (named by my little bro) and Gary (both goldfish).