I think sometimes people classify octopuses as mischievous when they are really just frustrated at their captivity. Are there any examples of their mischief/humor in the wild?

Why does it have to be more like us for us to leave it alone or study it in the wild? What's stopping us from performing these experiments in the wild? Put a jar of sardines with a lever in the ocean. So many of the experiments discussed do not need to be done in a lab for any reason.

It's hard to tell when a creature is delighted to be there. As the rest of this article has discussed, we don't know their language or how they show emotion. It seems to be interesting to say that creatures seem to be delighted to be here when we don't have a real way to tell.

This is a great aquarium. I usually don't like aquariums but I believe this aquarium is a very ethically sound one.

Maybe it's their unusual neuron layout in both their brain and limbs that causes them to die unusually early. It's difficult to maintain that level of function for more than a few years. I wonder how humans live so long.

I disagree with this conclusion because we are applying human logic about language to octopuses. We cannot speak their language and don't know how they communicate so there's no reason to assume that they don't have one.

It sounds like the neurons that control emotion are connected to color changing cells instead of facial muscles. There's no reason that one is more useful than the other. That's so cool that that's just how they developed.

So overall, an octopus is really just 9 different organisms working in tandem with one organism (the brain) having significant diplomatic power over the other 8. This might mean that an octopus in an ideal situation could have significant more processing power than a human. Each octopus is basically just a hive-mind.

Damn it people need to chill.

I disagree with him. I think they are an evolutionary response. For example, we cannot actually 'feel' wet. What we are actually feeling is a temperature adjustment that we've learned means we are wet. The first time we felt pain, we develop a cognitive process that says we don't like this and tells us not to feel this again. Pain itself is just a self-preservation mechanism to prevent us from injuring ourself. Some people like some amounts of pain. Some people can tolerate much more. And some people can't handle a little.

Because of the size and unique complexity of their brains, different octopuses will likely have different responses to being in captivity. Some might just give up and adapt to it. Whereas others might realize if they piss of their captors, they'll be let go. Shouldn't we stop captivating animals that can recognize and contextualize their captivity?

I think that the octopus clearly understands what the objective is. It seems unlikely that only one out of the three octopuses would not be able to understand the concept of pulling a lever for sardines. Maybe the octopus just didn't want sardines and refused to go along with the experiment. With a high level of intelligence, one would be able to deduce they are being observed and tested and might get frustrated. The octopus' actions seem consistent with frustration.

It's difficult to calculate intelligence based off neurons alone. As the article says, this is only a rough guide to intelligence. In humans, for example, you can cut out half the brain (lose half the neurons), and still have roughly the same functional intelligence. Neurons are used for more than just thinking. I don't think any of these factors about brains can quantify overall intelligence. However, the important point here is that octopuses have used a large amount of 'genetic energy' to develop a large brain. This may give them other advantages the author has not considered.