I wanted to talk a little bit more about Steven Pinker's "How the Mind Works", especially what he says about emotion and cognition. Pinker seems to want to dispel the idea that emotion and cognition are essentially at war with each other. He brings up the model of the triune brain with the newer neocortex built on top of the old reptilian brain, the newer brain in conflict with the older.

He brings up Spock as a fictional example of a supposedly purely rational being, or at least mostly rational (he is, after all, half human). Pinker says Spock, as represented, doesn't make sense. At least the part about not being emotional. He claims that Spock is motivated by intellectual curiosity; that he has goals, and thus has emotions. Pinker talks about how emotions and cognition are complementary, rather than in conflict. He talks about the evolutionary advantages of emotion.

However, while it's true that emotions have evolutionary advantages, which are pretty obvious when you think about them, it doesn't necessarily follow that cognition and emotion are necessarily always, or even mostly, complementary. In a rare plunge down to the neural level, Pinker talks about how much feedback there is between the newer parts of the brain and the older parts. He's right of course. But he should know enough about the neuroscience to know that feedback pathways can be either excitatory or inhibitory. Just because these parts of the brain, our intellect and our emotions, are talking to each other, doesn't mean that everything is going smoothly and that they're cooperating.

It also doesn't follow that having goals means having emotions. A chess playing piece of software certainly has goals. It may not be aware of them in the same way as a human, but it certainly has them, both short-term goals and long-term goals. But I don't think anyone would say a chess playing piece of software has emotions. I think emotional states are often a consequence of having goals. We are generally happy or pleased or satisfied upon achieving goals, and we're typically frustrated or angry or sad when goals are not achieved. In this sense emotion can help reinforce decisions made by the more abstract reasoning parts of our brains. But they can just as easily and more often than not, it seems to me, stifle or impede the functioning of the cortex.

How easy is it for you to carry out any kind of complex reasoning task when you're angry, depressed, or in any other kind of reasonably heightened emotional state? And it's not just emotions we would consider "negative". I can attest from personal experience, and from other people I've known, that people who are in love often don't make very rational decisions.

So I agree with Pinker's assessment that emotions are evolutionarily adaptive. But I think he downplays the inherent conflict between the two systems. I think they can complement one another, and often do, at least in healthy individuals. But they are also often in conflict, and were I building a brain or redesigning the human brain for modern living, I'd personally deemphasize the role of emotion, or at least its influence. I think in general we'd be better off if people did more critical thinking, especially if that thinking was unclouded by unhealthy emotional influence.