Octopuses, however surprising it may seem, can do all kinds of interesting things (although arguably maybe not, as some have claimed, predict the results of a football game): they can evolve with perfect ease in their environment (if, as I do, you struggle coordinating four limbs, imagine what it must be like with eight), they can unscrew the lid of a jar, which may seem rudimentary but is actually quite a feat on the scale of animal intelligence, especially for an invertebrate, and they can even learn that trick by observing one of their colleagues from afar.
Now, take a snail. Well, struggle as you may, you will find it very hard to credit the creature with any kind of extraordinary achievement: it basically spends its time either huddled up in its
shell, or slimily crawling its way to a better place. And yet, neurologically speaking, a snail and an octopus are very much alike: brainwise, they score pretty badly in the charts of creation. So, why can't a snail unscrew lids? Well, to put it bluntly, it ain't got no arms.
That might seem like a trivial answer, but actually points to a very deep truth about intelligence: that what makes an octopus intelligent is not its brains, but its arms, and the physical perfection of these arms rather than the complexity of the nervous system that controls them.
Of course, you might argue that the octopus itself is not really intelligent, and that it just has arms that allow it to seem intelligent, because they are designed so that they are physically able to execute difficult tasks, but you must bear in mind that a creature's intelligence (and that might well apply to humans as well), can only truly be measured in so far as it is put into action: in other words, if you act intelligent, you are intelligent, and there is no such thing as "being" intelligent in an abstract way.
Typically, take Muhammed Ali: at the start of the Vietnam war, he was deemed too stupid to be drafted by the army, because he scored too low in his IQ tests (though, later, the army lowered their standards...). When confronted by journalists on the fact that his low IQ technically made him "mentally retarded", Ali answered: "Well, I told you I was the prettiest, not the smartest."
And that answer might actually constitute an important clue as to the nature of Ali's intelligence, as seen by anyone who has watched his fights: Ali's intelligence was his long, swift limbs, his lightning reflexes, his fast, dancing feet. Ali was neurologically stupid, but his hands and feet had an intelligence of their own, embedded in their very fibres, and that is perhaps what made watching an Ali fight quite unlike any other boxing event, more like the aesthetic enjoyment one feels when watching ballet: Ali was not the best fighter, but the most beautiful.
Which leads us to our final point, which has to do with artistic creation: for centuries, philosophers have claimed that what made an artist great was, purely, his intellect, his capacity to put into aesthetic symbols (words, pictures, music) a certain number of ideas such as truth, beauty, harmony (Plato, especially, is to be blamed). But, if you ask most artists how they come up with their works, you will very rarely hear: "Well, I examined the idea of beauty, and I came to the conclusion that ideal beauty was best expressed by means of these words or colours or musical harmonies."
So, in view of octopuses and Mohammed Ali, perhaps a more satisfactory explanation would be: I danced these steps because my feet felt like it, I painted this canvas because that is how my eyes saw it, and I wrote this word because that is the way my ears heard it. An octopus' intelligence is his arms, not his brains, and in so far he is, as Duchamps would say: "Stupid, like a true painter."