Bright enough to do the moving-rock trick.
Updated Monday, June 23, 2008, at 1:14 PM ET
Aristotle didn't have a high opinion of the octopus. "The octopus is a stupid creature," he wrote, "for it will approach a man's hand if it be lowered in the water." Twenty-four centuries later, this "stupid" creature is enjoying a much better reputation. YouTube is loaded with evidence of what some might call octopus intelligence.
Read the rest of this really cool Slate article here...